Overhyped and boring?
As far as X-Com clones are concerned, I really haven't found a better one than UFO: Aftermath. See, what X-Com had wasn't just good gameplay, it had definite STYLE and ATMOSPHERE, something all other ripoffs I've seen has completely lacked either because of cheery, bright graphics, shit alien design or music lacking the creepy, suspenseful touch tone of X-Com.
UFO:Aftermath is atmospheric - you fight in broken-down post-apocalyptic citiscapes overrun by horrifying mutated freaks who're excellently designed and has sombre, creepy music, all of which does a fairly good job of recreating the "oh shit, we've landed on a terror site and are surrounded by aliens with blasters, I don't wanna leave this fucking space shuttle!" feeling from X-Com.
The two sequels to Aftermath disappointed me with their cheery, bright graphics and mongoloid alien design. Play the first one, download the mod adding a fuckload of new guns and enemies, be happy.
As for Extraterrestrials: It is an almost exact clone of Xcom made more than a decade after its release and it STILL manages to fail miserably in most areas. Shit graphics, NO RANDOMLY DESIGNED LEVELS, shit weapon and game balance, uninspired creature design, shit atmopshere. I wanted to love this game and failed. Avoid like gangrene.