This brings back some serious memories. The first time I ever saw a copy of the FASA TCS, I was at band camp ("There was this one time, at band camp...") and the trumpet player down the hall had a copy. I didn't get to play that night, but I decided it was a must buy, which started a decade-long love affair with that game and with Star Fleet Battles.
All in all, I think SFB was the better game, but it was hard to get the materials, so we tended to take what SFB stuff we DID have and create house rules for FASA out of it. By the time my friend's interest petered out, our house rule manual was probably thicker than the manual that came with the game.
Good times...