Crashplan
 

Will an internet backup service like Crashplan that's always running in the background (for the most part) interfere in any way with SD operation or transfer speed?

It shouldn't - it's something I've done myself and I haven't noted any issues.

I keep getting occasional errors when cloning my boot drive since I've started using Crashplan.

Try excluding that folder (/Library/Caches/CrashPlan) from the copy using a copy script, and do a single erase-then-copy backup to clear things up.

OK thanks. Doing that now, will see if that does the trick.

Seems to have fixed it. Never did an exclude script before, could be easier but it does the trick. thanks!