>>Another thought though, with either the 7300 or DP, you shouldn’t need another amp. I wouldn’t waste your money. The 7300 has incredible current.
I have to second this... hadn't realized your receiver was going to be something like a 7300. Between going with a 7300 vs. a (probably) less expensive 635 with a couple of monoblocks I don't really know which would be better... but if you're thinking about a 7300 I certainly wouldn't bother getting external amps for a while... the 7300 is quite a beast already.
I'm running a 630 with M60s and haven't felt even the slightest urge for more power yet. When I move into the new house the HT area will be quite a bit bigger so I might feel the need for power then... but by then I won't have any money anyways so it doesn't really matter
Chesseroo's point that an external amp will also help when driving 4 ohm speakers is also a good one... although HKs are pretty good with 4 ohm loads.