i never use just a sampled loop on its own but will use them in combination with sequenced drums, for instance adding a sampled loop of tribal percussion behind my sequenced kick, snare, hats, etc.
but i won't use sample cd's i try and find loops in different places like on old charity shop/car boot records (much cheaper!).
sometimes i'll just extract the groove from a loop and apply that to a sequenced part.
I think it's best to try and get away from using loops too much, just let your imagination run riot in your key/drum edit window and see what happens