Buying a new coffee roaster: from Behmor to Quest

This post is a summary of the journey I took in researching “prosumer” level home coffee roasters. It took me a long time to find the information I needed to make a decision, so perhaps these notes will be helpful someone in a similar position. I ultimately got a Quest M3s from Coffee Shrub, of which I am really satisfied. I’ve done about 10 roasts on it so far, and am beginning to get the hang of it. The first three were truly awful, though!

Feeling frustrated with the Behmor

After 18 months of roasting on a Behmor 1600+, I was hooked on home roasting. After spending many hours reading home-barista I was also convinced that the Behmor didn’t offer enough data. Thus I began a journey.

My first crack at resolving this was to modify the roaster to include a bean temperature (BT) thermocouple probe. I used this excellent video as a guide.This worked okay, but I found the positioning of the thermocouple to be finicky and very difficult to get reliable results. I also noticed that the BT measurements seemed highly influenced by whether the heating element was on or not. Even with tons of curve smoothing, this produced a sawtooth Rate-of-Rise (RoR) graph with wild swings that I found really hard to read:

I briefly considered a design where the BT probe would be more consistently located, but abandoned this as the design of the roaster makes this pretty challenging. Instead, I began to search for an upgrade.

What I wanted in a new roaster

The first thing I did was try to map out the market and make some decisions about what I was broadly looking for:

1. Reasonably small size. I live in apartment in Chicago. I don’t have a garage to host a giant gas roaster, nor do I want it taking up my living room. Smoke exhaust would consist of the range hood or an open window, which also puts some limits on size. As an aside, for anyone upgrading to a roaster like I have from the Behmor: you need some ventilation. The Behmor has its shortcomings, but it’s amazing at suppressing smoke.
2. Electric. I wavered on this but ultimately decided on going for an electric roaster. With the exception of the Bullet R1, the downsides of electric are twofold: limited max charge weight and greater delay/latency between changing heat settings and seeing the result. The upside is obvious: no gas hookup or need to store a propane cylinder. I don’t want something that will be unsafe to use indoors or have a large volume of accessory parts. I also read some reports that gas roasters produce more smoke, but I cannot corroborate this.
3. Under $3000, ideally under $2000.More than that just seemed ridiculous for a hobby like this.
4. Works like a commercial roaster. One of the annoyances of the Behmor is that there’s not a ton of literature about how it roasts. It’s sold as a “drum roaster” but it’s a mesh drum with radiant heat and low thermal mass. It doesn’t roast much like a commercial-style solid drum roster. I found it difficult to apply methods I read about on the Behmor.
5. Capable of roasting at least 250g of green coffee in one batch. Initially I really liked the idea of roasting larger batches, but I realized I don’t have a major use for this. My wife and I consume about 200-400g of roasted coffee a week, depending on my travel schedule. I do roast for friends occasionally, but not frequently enough to optimize for this.
6. Capable of roasting back-to-back. With a preheat, roast and cooling cycle, the Behmor took about 40 minutes to roast a single batch of coffee. A back-to-back roaster can do three in that time. I generally like to have a few different batches on hand, and this helps mitigate a smaller max charge weight.

The options I found

This really narrowed it down to three main contenders: the Bullet R1, Quest M3s and Hottop 2K+ with a few less likely outliers. Here’s a summary of the information I gathered in making this decision:

Roaster	Price	Max charge	Eliminated because
Hottop 2K+	$1100-1600	300g	Don’t like aesthetics requires replacement filters
Quest M3s	$1,400	~250g
Bullet R1	$2,800	1000g
Huky	$1600?	500g	Gas powered
North / Mill city 500g gas	$5,000	500g	Gas powered too expensive, too big
North / Mill city 500g electric	$3000?	500g	Doesn’t exist anymore? Too big
Kaldi	varies	varies	Gas powered
Yang Chia	?	120g	Max charge too small
Arc Roaster	$3,750	800g	Too expensive

Why I ended up getting the Quest

The real decision was between the Quest M3s and Bullet R1. I chose the Quest. Here’s why I made the choice I did:

1. Same results in the cup. A number of folks have upgraded from the Quest to Bullet and report slightly better results. Accounting for confirmation bias, I take this as no difference. I asked this question on home-barista and got a lot of interesting responses.
2. Mechanically and electrically simple; I can repair and modify it easily. One thing I love about my E61 espresso machine (Quickmill QM67, an older version of this machine) is that I know how to fix it and modify it. The same basic mechanism has been going strong since the 1960s, and parts are available from numerous manufacturers. I had an E61 heat exchanger (La Nuova Era Quadra) before it for which finding parts in Canada was nearly impossible. I repaired it a number of parts from other manufacturers. Having taken a peek at the Quest internals, I think this will also be true for it. 
   
   Conversely, the Bullet is certainly not a machine that is likely to be repairable with off the shelf components. I have read that Jonas Lillie, the inventor of the machine has gone to great lengths to source high-quality long-lived components, and surely that counts for something. But it won’t work forever. And can a machine with some plastic parts and full of ICs and surface mount capacitors really last as long or be as easily repairable as one made of stainless steel, wire and a few generic components? I doubt it.
3. Doesn’t require closed-source vendor software/firmware to run. This was the real dealbreaker for me. I really couldn’t get over the fact that the Bullet R1 requires custom vendor-specific software to run. When buying something that needs this, you’re really investing in the manufacturer, too. If Aillio goes out of business or loses interest in supporting your roaster, who will update the software to keep it compatible with the latest version of your OS? If it’s closed source, potentially nobody. This is a machine that heats beans until they turn brown. I just don’t want it needing a software update. 
4. Automation didn’t seem very important to me. Yes, the Quest does not support automation. It’s a manual machine. I could modify it to be automated, but I don’t have that in mind. Perhaps my mind will change as I zero in on some great roasts and (perhaps) struggle to replicate them, but for now, I’m happier turning knobs than I am programming inputs. This encourages experimentation, which is what this is all about.