Even with all the pirates around me, I'd like to say that online demos are pretty cool because I can get contents for free without going anywhere. While waiting for my Street Fighter IV I've been playing Resident Evil 5 for several times. Here's how my experience explores:

1. Oops, this game is so goddamn hard! I want to aim with my wiimote!
2. OK lemme try to play online... Damn. My partner must be very Orz.
3. After playing single for several times, it's not that hard. All stages cleared now.
4. Getting online again. Co-operation RULES!!
5. This game is too goddamn easy!

Thus I'm looking forward to RE5 as well. It's gonna be very interesting, I guess. My next challenge will be F.E.A.R.2 trail :)