I'd second the Arena comment, but I'd say go for the full set not the Lite.
Better than MT-30 and 3005SE for films, (more detailed sound), from my demos. I thought the MT-30 sounded dead at the top end in comparison to other speakers. Also the KEF 5005s pretty much matched the Arena for films, it was just music they fell back on, so they might be worth a look. Never heard the Monitor Audio so can't say how these stack up.
BTW find the bass from the sub in the Arena plenty good enough, and nice and tight. Not boomy, obvious, or agressive. Didn't feel as if I was missing anything bass related from the Arena in comparison to the MT-30 when I demod. The PV1 was better than the KEF sub for music by some distance though.
If I was you I'd flog the MT-20 while you can get a decent amount, and get the Arena while it's still available. As it's discontinued it'll probably cost you about the same as a PV1.