I have owned a DM8 and currently own a DM9.
I have shot someones PM7 before and i'll be frank, I loved it!
its a really solid gun, absolitly nothing wrong with it, it shoots balls at 10bps at 300fps, I'm seeing guns like DM9's Ego09's and Luxe's as luxuary Items that people don't need, but have just because they want to keep up with having new shiney gear!
Differances between the DM9 and DM8 are;
-DM8 is heavier
-DM9 has a new trigger adjustment, which means you can set it better
-DM8 has a larger trigger frame, so you can wear gloves whilst shooting it
-DM9 has a longer snatch grip
-DM8 has the on/off purge under the barrel (i personally dislike this, but is a good safety feature)
-DM9 has a smaller bolt meaning better air efficiency (and this is true, because i use a small 0.8L tank so i can tell the differance)
-DM9 have the new and better detents by a long way! Although you can get these for DM8's
-Both guns have differant milling, DM9 being the one with less curves on it to cut down weight.
Other then that both guns are similar, they have the same boards, same hyper 3 reg, use the same barrel, same eyes and same solinoid. You will always get fantastic support from Dye no matter what happens to it.
Second hand DM9 around the £500-£600
Second hand DM8's are like gold dust, they sell for around £330-£360 Second hand
You get what you pay for, personally, if you have the cash to get a new DM9 go for it, but otherwise, save your money and buy paint instead
PM's rock my friend, shame the PM8 was the last of the line...
GET A PM8! there balls cheap and are basically DM8's - i expletive you not same reg, same solinoid, same ul frame, same board slightly differant bolt but for around £250-£300 get a PM8, they are magical guns!