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.