Hostels in Rio

Does anyone have any experience with the big party hostels like Che Legarto (in Ipanema and Copacabana) and Mellow Yellow?

I stayed in "hostel alley" in Ipanema last year and met up with loads of cool people who used to go out to mix with the locals in non-touristy clubs and bars.

Just dont want to end up in a hostel with a Cancun-type atmosphere where people never venture out of the hostel bar.