Okay, if I were to choose from only those two, I'd pick the first one. Few good quality cinematics over many low quality cinematics.
Because the player would be really pissed off, if there are a lot of cinematics, and their quality sucks. It would make you think "Why did you even add cinematics in the first place?!" or something of the sort, while if you pick the first one, the players would think "Wow, what an awesome cinematic! I expect more to come," which makes players more eager to play your map, an awesome cinematic is a prologue to an awesome game.