no. not day to day things. but, when i add an app to osx, it always leaves the other apps alone* and does not disrupt the os or other software. *AU issues in fcp is an exception. adding aftermarket AU to a DAW via user library will cause fcp to no-launch. creating a seperate user for fcp and having no AU in new user library is a PITA workaround. i am sure there are other exceptions and someone will have had a HUGE mac PITA issue. on the pc i find this to be less than true. i spent a LONG time with tweakxp.com or whatver the name is to get the pc to run great (yes, great). however when i add a new app to XP i really have to think about whether or not to do it. sometimes it can take a LONG time to get things working well again. adding protools 6.x to xp resulted in protools running fine, however the install took out tmpgenc completely. wouldnt run. fussed with it for a while, dumped protools to get tmpgenc to work. adding a video card - getting all drivers/direct X/apps to work in harmony is a comprimise at best sometimes. what works for one may not work for the rest. adding asio for one app may cause another app to lose contact with its audio card. none of this makes me mad, in fact i have no OPINION on it at all. just observations. it DOES INDEED take ME a lot longer to get the pc to behave, especially when adding apps/changing drivers etc. my pc is invaluable to me. pry it out of my cold dead hands. i feel the same about the macs. right now my pc works without issue. it has for a while. but i do not add apps to it unless i am prepared to deal with comprimises. now if you would like to have some mac problems, try installing FFMPEGX and all its supporting libraries. good luck. got about a month? however installing x11/ardour/jack (pretty serious {censored} here, no?) results in a pretty easy to live with situation. if you can read, you can do it. and it wont interfere with anything else. i have no OPINION on these machines anymore. i cannot recommend one over the other. i can only relate my experiences. others may have entirely different experiences. this is not the case at my summer job (IT hell - fortunately i sit back and watch IT go through hell)