Use it every time I fly (except circuits). Only thing I don’t like about it, is figuring out the TAS – the pressure alt and temperature gauges are so small, and the increments so large, it’s easy to be off quite a bit, if you’re not careful.
But the best bit is when you show it to a prospective new passenger – they look at it, look at the bashed up old rental you’re about to get into, and generally shake their head in disbelief