I'm not a big fan of backline only... you really need someone to balance all the sound up properly... but everyone I spoke to thought it was pretty good, including Mrs SJ who tells it like it is!
I got collared by a bass-player afterwards... a Warwick Thumb player, in fact... well, he thought the bass sounded fine, and we both agreed it was hard to get a bad sound out of a Thumb (well we would say that, wouldn't we?)