Tablet for college - Asus T100/Venue Pro/Surface - Advice

Hi everyone !

I know that there have been already a few threads about this topic, but i still need your help

I looked at a few tablets and i think the Asus T100 is nearly a perfect fit. But it does not have a digitizer. The HP Omni 10 has neither a digitizer or a keyboard. i fear that the venuepro 8 might be to small for my purpose. i really like the surface pro maybe i can afford a reconditioned or used one ?

What i want is :

- Windows OS Pro (i want to use a statistic program as well)

- ~ 450-500 euro (it can be a refurbished or used one too)

- for marking and editing documents, browsing, watching videos and it should be able to handle a statistic program

- digitizer would be great- keayboard too but i guess you cant have both for my price limit

Does someone know alternatives

Help would be greatly appreciated !!!!