Regarding the pumps... I haven't used them, and wouldn't. I don't like the idea of using knock-offs for any situation where electricity is submersed in water. The importers don't usually have the electrical standards we do here. At the very least, if you are considering it, make sure it carries a UL and/or CSA certification.
The lamps... well... put it this way... the expensive lamps are expensive for a reason. More than anything else, when you buy an expensive lamp, you are buying a lamp that has substantial quality control and R&D invested in making sure it's a quality, long lasting produce. Those knock-off lamps may well work fine, but they may also suffer a premature degredation that doesn't set in until well past the usual 30 day return policy. I've not used them, but I'm not going to tell you not to, just to be careful and don't set your expectations too high.