I figured my first comment would liven up the conversation. Yes, we have discussed the vernier throttle before and it mostly boils down to personal preferrence or in my case, what was on the airplane when I bought it. However, having flown the 170 with the vernier throttle for almost 30 years, I really like it. It functions smoothly, I never have to fiddle with a lock before and after adjustments are made, and precise adjustments back to the exact desired RPM without over-shoot can be made when the digital tach gets 1 rpm off.
The vernier throttle is most useful on approach. For instance, when on a stabilized approach, tiny precise adjustments can be made to adjust glide slope that even a fixed-pitch normally aspirated carbureted engine will respond to, as opposed to having to unlock, adjust without over-shooting, then re-lock the slide throttle. The vernier wins hands-down.
Again, if someone doesn't want a vernier, don't get one. But if you already have one or like how they function, they are a good mod.
By the way, I just had a vernier throttle installed in the 195 last year. You need that kind of precision with a digital manifold pressure guage accurate to 0.1"Hg.
Before that, I had the original softball-size throttle. I felt like a Little League pitcher every time I had to make an adjustment.
