Hi, I know the feeling. I'm presently wading through 10 or so programs myself looking for one that will mirror and sync my large external bu's via usb as well as saving from 3 computers to them.
So far I've narrowed it down to SyncBackSE, ViceVersa Pro, GoodSync Pro, SmartSync Pro, AllWaySync & Advanced Directory Comparison & Sync. All 6 will find files buried in the target down a no. layers unlike some. ADCS doesn't save profiles unfortunately. ViceVersa & SyncBack purport to handle locked or open files but I haven't tested this yet. All have good interfaces once you get used to them. AJC Directory synchronizer...find the preview a little impractical but it can direct an odd file to a different folder if in doubt.
Programs I have discarded are Data Sync...forget it, PeerSync... very comprehensive but too expensive and deadly interface if you make a mistake, Novosoft Office BU...no preview I could find so forget it. .
MS SyncToy 2 beta ok for a basic program since it's free and there are cut down free versions of GoodSync, AlwaysSync.
Cheers, foxtrot64