I have Vandersteen model 2 signature series iii. Very revealing and can show you the difference better amps/sources give you. Not sure how your series speaker responds to gear, but also not sure why posters are saying too much amp for speakers- to me that's like having too much horsepower in you car-may not be able to use the excess horsepower all the time, but sure is fun to have anyway! You can always upgrade speakers later if they sandbag your system.
I have had a bunch of integrateds including Rogue Cronus magnum ii (tubes), a Krell 400xi, Krell Vanguard, a Mcintosh 6900, Naim Supernait 2, Ayre ax-7 and finally for the last year, an Audio Research dsi200. The key for me was a passive pre amp with Vandersteen. The ayre ax-7 had a passive pre, but ran out of steam at higher volumes for me.(may have had another issue internally tho) The AR is my keeper which has a passive pre as well, and has the power for very accurate, deep bass that the rogue tubes didnt have. It showcases the Vandy's "honest" sound as well. Friend of mine ran a Creek 4330 se with his model 2's and it was fantastic as well(also a passive pre)
Johnny Rutan from Audio connection recommeded to me the Aesthetix mimas, anything AR, as well as the Ayre ax5-twenty. He is a Vandersteen guru and you could reach out to him for advice possibly. Very nice guy. These are my findings- hope it helps!