I've had very poor performance with r24 built from git on linux. Lots of low difficulty shares and nonce issues concerning already being sent.
[2015-01-05 00:20:18] nonce 6537ae00 was already sent 2 seconds ago
[2015-01-05 00:20:26] nonce 47dd5f01 was already sent 2 seconds ago
I was only getting about 8 Mh/s effective hashrate at the pool with r24 as opposed to 10.5 Mh/s with r23. I'll be sticking with r23 for now.
Some days ago I added 2 nonce sending in quark, but it had some bugs (double sending) and I reverted the changeset.
Make sure that you build from the github version that is tagged with the "release 24" changeset. Commits before the tagged release could have sideeffects. And commits after are not tested properly and could have errors.
Yesterday I fixed a bug when running benchmarkmode (Run the benchmark for a while and it starts to print 100 times as much text to the commandline). Seems to work, but untested on the pool.