Hi,
Whatta ya mean 'little set-up' ??!!! You tried lifting an ampeg svt300 up in a hurry ??!! Lol. Yes, the cab can handle 400w at 4/8 ohms, in this instance it was 300w (and a deafening 300w at 4 ohms).
I used that particular set up for about 5 gigs last year (mainly pubs/clubs) with a 3 piece hendrix-style tribute. To be honest it was frighteningly aggressive fender pbass rock - it really did valves justice. I also did a few rehearsals with another band, and the ebs shone using a crown xls power amp.
Eventually (5 gigs later) I bought an Ampeg SVT pre amp and the EBS was history!!! I occasionally do these mad things....
The Marshall 4x12 is an excellent bit of kit - whatever I've played throught it - it's always sounded excellent (GK's, SVT's Hartkes', Eden's, Line6's).
Matthew