@mstrongbow, I am on the most recent 1.3.0 version. Trust me, I've been staying on top of it 
Definitely never seen anywhere near 5% rejects 
I have also had my pi reboot 1-2 times daily. I thought it might be because of the USB hub, so I replaced it with a powered one. Interestingly, the blades seem to be running a few degrees cooler after the switch, but still rebooting. It doesn't bother me too much though - it reboots quickly, so my overall hashing power isn't affected very much.
Definitely never seen anywhere near 5% rejects I have also had my pi reboot 1-2 times daily. I thought it might be because of the USB hub, so I replaced it with a powered one. Interestingly, the blades seem to be running a few degrees cooler after the switch, but still rebooting. It doesn't bother me too much though - it reboots quickly, so my overall hashing power isn't affected very much.