I have many fire sticks. As well as an original Fire TV, and 2nd gen Fire TV Cube. All work great. First gen sticks are really slow now though; don't use them really anymore (sometimes bring them while traveling to use with hotel TV's).
I bought this new lite version because I have a portable projector that I use with fire sticks. I usually used the old gen 1 fire stick, which again, was slow. This new firestick is super fast (equal to the Firestick 4k) and works great with my projector. While using the projector I have no TV or Volume to control with a remote; so, I didn't need those functions. My projector also only puts out 720. So again, no need for the 4k. If you want a Firestick that will last the longest, and provide the best picture, get the 4k stick. But, for some people, like for my uses, this lite version fits my needs perfectly.