I play the demos first. If it's something worth having, then I have it, and that's the way I roll.
If the demo doesn't make me want to play more, then I won't even waste my time thinking about buying it. But if it gets me and I think I could have fun with it, it's a wrap, and there goes up to $15 to fuel my need to not feel boredom and my need for novelty. Like that goddamn PixelJunk Monsters on PS3 - it ate my soul, man. And it was
a fucking demo. After kicking that one around for about 4 and a half minutes of saying, "Well, that was a lot of fun...I wonder if I should pick that up?", I finally decide to and it eats my soul for WEEKS. And now I feel the same way about The Last Guy. I play the demo, find out that it's a lot of fun and charming as hell, and I want to spent another ten bucks to satiate my desire for cheap thrills.
And no, I don't just d/l the newest game, good or bad. I try them all, granted, but very few make the cut, considering what all unadulterated crap is out there. Merv Griffin's Crosswords? Blow me. Even that Doritos game sucked, and that was free, and I'm SO glad for that. I want to know how that game became the winner of any contest, it's like playing Blast Corps in the 7th circle of hell. The only other free games I've ever gotten from XBL were Aegis Wing, which was a pretty good shmup considering the relative inexperience of the team that made it, Undertow (which I would have NEVER paid for), and Renaissance Faire road-building simulator Carcassone (same law applies).
But through all of this, there's stuff like SSF2THDR, Rez HD, Triggerheart Excelica, Ikaruga, Castle Crashers, Catan, the original SoulCalibur, Braid...there's a lot worth playing (and a lot that was already on DC, but I want my 1080, you dig?). Add in the fact that MvC2 is on PartnerNet (XBL's special developer-only, invite-only, NDA-signing backdoor funhouse) and there's another wad of cash that I'm willing to spend to twerk some faces online.
How do I afford all of this? I only pay for my XBLA games, but I get the MS points at discount. Out of all those (disc-based) games I just listed, I own 5 out of the 30 I listed (that were on disc). I play the rest for FREE, no torrent, all legit. But how I do that is a secret I keep to myself. Blah.