If he's a good friend you trust and needs the money, I say go for it. If not, just be patient and build a collection from scratch. Controllers and L4D2 are cheap and plentiful and if you're really aching for that RE5 bundle, that'll cost ya a little more so better to put the funds into the system you really want then build around that later.
You can always buy more controllers/games, but once you buy the system your options become much more limited if it's not the one you truly want.