Bottom line first - go with the windows 8.
1) uSoft will soon be coming out with upgrade (8.1). How well it alieviates user complains is up for grabs.
2) have Win 8 on a i5-2410m Laptop and currently staying with 7 for my desktop. Primarily cost factor. will go to win 8.1 IF upgrade price is reasonable.
3) Keyboard and mouse is NOT a big issue, Just get Start 8 and it will look and FEEL just like Win 7 but with the FAST boot times of windows 8. Win 8 cut my laptop boot time from about 15 Sec to 8 seconds. NOTE: There are some free "Start Menus" but for only 5 bucks start 8 is hard to beat.
4) Win 8 seems to be HATE vs LOVE acceptance among windows 7 users, close to a 50/50 split For thoes that were "stuck" with it (New OEM System purchase). Most have learned to addapt to it, some (unknown %, but probaby small) have hated it and "downgraded" back to windows 7.
My own experience: On Laptop, the only problem(s) I've had:
... On occassions tried to use my NON-touch screen as if it were a touch screen (Have a touch screen tablet). - LOL
... Only found one software app that would not run (work related, not a common app).
... Intsalled the latest Total theatre Program (at that time) for watching blu-ray DVDs/movies. Boot time jumped from 8 sec to almost a minute - OUCH. Uninstalled it and went back to old program. They have updated it, but have not tried the updated version yet.
Added:
As Geofelt indicated, you can go to Best buy and "play with Windows 8.
BUT bear in mind that this will not be with Start 8. With Start 8 There is Very liitle difference in look and feel.
... Old start menu is Back.
... Power OFF short cut back
.. Can even find uSofts Backup (to create a system image) without jumping thru hoops - For some STUPID reason usoft Bured this EXCELLENT app.
When My laptop boots you would think I'm using Windows 7, But with a mouse click I can revert to window 8 metro. Also as stated windows 8.1 will be out shortly - Free upgrade for windows 8.0.
For users with win 7, Very little reason to upgrade. For "NEW" OS purchase, Most would be better served by going with Window 8.