Dunno much about weight gainers. But the fact that most if not all of them have in common is the crazy amount of calories they pack in that stuff. Somehow, doesn't look that all appealing to me. Saying that, I know a lot of guys who swear by them. So there you go, I suppose you could try a few, see if works for you.

For me, I'd go for eating well, enough rest/sleep and train hard would give you results (in time)