I've been breaking chains for 30 years with no ill effects, but these have been 5-speed to 8-speed chains. Currently use SRAM 8-speeds chains, but have never used the narrower 9 or 10-speed chains or the ones that require replacement pins when broken. The PowerLinks are certainly more convenient for general cleaning purposes, though, and I'd recommend them. You will need a chaintool for replacing a chain, though, as they have to be cut to length. I wrote a very detailed description of how to break and install a chain with a chaintool in this thread: http://forums.teamestrogen.com/showthread.php?t=9930 assuming the chain has reusable pins (not the kind requiring replacement). You do need to know how to remove a stiff link after re-installing the pin, but drilling a pin in and out shouldn't compromise the chain flexibility or chain life in my experience. Though the ultra-narrow 10-speed chains may be a somewhat different beast.