I patched up to 5.01 a couple of weeks back and haven't noticed any differences at all. I liked the look of the new v.5 interface/theme but unfortunately the markers were less legible than the old v.4 theme, so I had to revert back. I use the markers to remind me of chord changes for overdubbing.
A seamless update here too. I was a little dubious so updated my laptop before my main PC and all worked perfectly. So the main recording PC was updated a couple of weeks back and then patched to 5.01 when it was released and so far experienced no negative effects from the update.