Best 3D printing Filament brand

I have a MakerBot Rep 2, and have been using the filaments from makerbot but have been wondering if the off brand filaments were as good as the makerbot ones. I've heard that some filaments break print jobs or causes bubbles. I haven't had a problem with the makerbot ones but I also can't afford the doubled price of the filament compared to some other websites. Anyone has any idea or if anyone does use off branded filaments? Thanks.

I would probably stick to MakerBot's filament if you are using one of their printers. At least that's what they recommend.

most of the makerbot guys rave about www.toybuilderlabs.com. its supposed to be some real good stuff and pretty well proven in MB machines