Ok (no) shoot out here sorry, but i was lucky enough to play both cabs through a Peavey 6505 for a good few hours today.
the Marshall DM is scary good! shat all over the Blackstar series 1 cab.
both fitted with vintage 30s and the Blackstar being an Ooversized cab
it sounded extremely boxy and fizzy with a loose low end.
the Marshall gave the 6505 an almost organic sound smooth mid's
crisp highs no fuzz! and an extremely tight low end.
anyways this being more of a recommendation than anything!
try out these Marshall DM cabs there f""""" sweet!~
id stay away from Blackstar i know the price is appealing but anyone considering buying one please put it head to head to another v30 cab on the market it wasn't too hot sounding tbh
again personal observation, i'm sure if i could post a clip ud agree anyhooo
with all said i also played through the Blackstar 100w head and this was extremely good sounding with a'lot of tasty features worth checking out.

both fitted with vintage 30s and the Blackstar being an Ooversized cab
it sounded extremely boxy and fizzy with a loose low end.
the Marshall gave the 6505 an almost organic sound smooth mid's
crisp highs no fuzz! and an extremely tight low end.
anyways this being more of a recommendation than anything!
try out these Marshall DM cabs there f""""" sweet!~
id stay away from Blackstar i know the price is appealing but anyone considering buying one please put it head to head to another v30 cab on the market it wasn't too hot sounding tbh

again personal observation, i'm sure if i could post a clip ud agree anyhooo
with all said i also played through the Blackstar 100w head and this was extremely good sounding with a'lot of tasty features worth checking out.