If you looking only for VAG + BMW , then VVDI2 and VVDI prog is way to go. No need any other tool. In VVDI2 you have also programmer similar to Tango that you can make keys buy dump, but 90% of VAG and BMW can be done by OBD in VVDI2.
VVDI programmer don’t have OBD it’s only for bench programming.
Good for CAS4, FRM, EZS, EWS4 and many more.
VVDI2 tests on BMW:
Xhorse vvdi2 is a really good tool for BMW and VAG; it makes keys over OBD (90% of VAG and BMW (can be done by OBD in VVDI2) and includes all the VVDI functions