I've done a few of the routes at the cave sector at Caimari (which is where the bouldering is). Apart from a couple of variations and sitters, the boulder problems are all the starts to the routes (a bit like the problems on the RHS of the Tor). Unlike the RHS of the Tor the problems generally aren't the cruxes or even the good bits of the routes. You drop off just as the routes start getting good.
So if you're nearby anyway and want to get a bit of climbing in on your own it would be ok, but I wouldn't go to the crag to boulder if there was an option to climb the routes (which are very good). The landings are flat, hard, rocky/dirt - like the bottom of the Tor.
However, a few km up the road at a place called Lluc there is lots of proper bouldering, on boulders, apparently. Not been but there is info on the web if you use some google-fu.
