This pickup sounds decent and seems reliable enough compared to other systems in the same price range. This runs well and stays in place after a fairly simple installation. There is one problem, though. The output signal is very, very low on this pickup. You'll have to crank your mixer or amp half the time for no, to me at least, obvious reason.
It's fine for gigs in a lot of ways, but make sure you bring a preamplifier or something else to seriously boost the signal. If you want a clean double bass sound I'd recommend an active condenser mic on a goose neck instead :)