Thanks for sharing!
I don't have a probe in the MET position on my Quest, just the BT and ET. With that profile, my ET gets to about 260° when the BT is at that drop temp - 236°. I'd imagine the MET gets hotter still. I've done hundreds of roasts in my Quest, without ill effect. I am, however, a big stickler for not stressing machines too much. You can easily adjust that profile drop temp downward to a level that makes you more comfortable if you like. My machine shipped with the analog thermometer in the BT position. Given that, I'd
imagine that 250° guideline would be for the BT reading, which I don't let get over 250°, so I personally don't worry too much about it. Just my $.02.
That profile is geared for multiple batches. If the Quest had a built-in thermostat, it might be easier to just set the machine to your desired drop temp, and let it run hot for a few minutes when warming up, and then dump beans. As it is, though, it's usually a guessing game as to how much heat the metal housing has "stored" in it, which means the first roast will always run cold. If you roast back-to-back, subsequent roasts will be much closer to the target temps when using those control values. You'll learn to make adjustments to heat and fan to compensate for the first roast, or just make a separate profile if you don't roast multiple batches, or want finer control. What I usually do is let the temp rise for 5-10° higher on the first roast, then drop the beans, and make the other AMP control adjustments early or late, depending on what I need to stay on target with the BT curve. I've also designed that profile to allow some "wiggle" room with the fan - which is important to be quickly adjust chamber temp if a curve drifts too much. Using the amps takes a while to see an effect - the fan is quicker to produce results.
Yes, my Amps max out somewhere around 13 as well. I have that curve's max level set to 15 to make it easier to emulate the scale printed around the potentiometer. To me, 15 just signifies max.
As for matching the curves... you may find you hate my profile.
Most people would argue that 13 minutes is too short a roast time. For me, though, I've found that as long as I can stretch the crack time out, I love the clarity that a shorter roast time gives to the cupped taste. Stretching the crack time out allows this without sacrificing depth of flavor and sweetness.
Let me know how it cups!!