Hiya.
FASA, hands down. One of our most remembered campaigns (any game). We played in our friend Dave's basement (he died a few years back...great guy...miss that big lug...). Anyway, his basement room was rather large, about the size of ToS actual bridge. It also had a bar in it (full). With the FASA version it had all those cool player-hand out sheets for Navigation, Engineering, Weapons, etc....and the Engineer had to dole out energy 'points' to other stations. Everyone moved little 'chits' around on their chart, taking power from weapons to boost shields and stuff like that.
We had the whole basement laid out like the bridge...tables, chairs, lighting, etc. A big white board was the "screen" and the GM sat down in front of it and to the side. Our engineer had the 'bar'; it had just enough bar/cupboard blockage that he kinda sounded muffled, so it gave the sense of him being "down in engineering". We had props too...even one of those little "scientific viewfinders with the blue light inside" that Spok always looked into and said Fascinating. When we got hit, the GM would raise a hand and say "A solid blast the to the port side!", and all of us would 'react' to it, jiggling in our seats or staggering and grabbing onto a table/bar (engineering). A toy "star trek noise maker" (played ST sounds like phaser shots, comm opening, red alert siren, etc) was used to great effect!
That campaign was an absolute BLAST! We had a hair-net wearing, toothpick-chewing Hispanic engineer, a demure, charming and almost narcoleptic communications officer, a studly, HUGE bodybuilder doctor-captain (that was my character), a fortune-cookie fortune-telling efrosian (?) navigator into Tai-Chi who sounded like Doc fromBack to the Future (and he kinda looked like him too)...and others.
Of all the RPG's I've ever played over three and a half decades of RPG'ing (and that's saying something!), FASA's Star Trek rates at the very top for a "game that feels like it should". Even if we put a "bit" more into the game than others...it gave use the rules to do so. Good times...good times...
^_^
Paul L. Ming