Anyone do an in-place upgrade from Win 7 to 8 to 8.1 on T61/X61T? Any Issues?

Anyone do an in-place upgrade from Win 7 to 8 to 8.1 on T61/X61T? Any Issues?

Yeah I know people are gonna recommend a clean install but I am going in those 2 steps so that I don't have to reinstall reconfigure a lot of things.

I have so far using the Win 8 upgrade compatibility app scanned out most issues it shows except one "Lenovo Auto Scroll" -
http://forum.thinkpads.com/viewtopic.php?f=67&t=115151
I had some issues eliminating it but I think I might have found the source of what installed it 'The System Interface Drivers" had the OSD and this thing in built (if I remember reading the text file correctly).

Anyone who went for an in-place upgrade please point out/ share your experience/ good.. bad.. any issues.. ? Do let me know.

Thanks.