I really like trim.
I've been a working pilot for years. Far longer than I've flown RC planes. In learning to fly - you're taught how to use trim to remove control forces and better allow the aircraft to fly hands off in a stable manner. Elevator trim is one of the most frequently used controls in an aircraft, especially given the speed range and operating envelope that modern aircraft routinely operate within. The trim requirements for slow flight in a gear down and dirty configuration are far different than for cruise, and configuration changes make the relationship of trim with speed not always linear - so frequent pilot input is required. In learning to fly RC - I was self taught. I sat out in empty fields, and tossed airplane after airplane into the air, and slowly figured out how to fly them. What baffled me however was the trim control on most remotes. These tiny trim buttons buried either next to, or just underneath the sticks are hard to find when you're airborne and keeping eyes on a model plane. I wanted something that I could use while keeping my fingers on the sticks, and trim away any continuous stick inputs quickly and easily. Enter the sliders. In flying my model aircraft, I mapped and purposed my sliders. (Right Slider is shown in the photo below - it's an easy reach for your index finger.) My right slider is now my trim. In my mix, I have set the neutral detent as pitch trim neutral. Inputs on my slider direct a setting of elevator trim up to 40% throw in either direction. This allows for an airplane of a given CG to be rapidly be trimmed for stable flight throughout it's speed range, and even inverted. My left slider I use for flaperons. Both work well, and now see frequent use as I fly my models.

I still haven't figured out what I'll use my old pitch trim switches for. Any suggestions?