R-Type
R-Type Leo
Gunforce
Dragon Breed
The only one so far that cost me more than $50 was R-Type Leo, so I figure I've been doing pretty good

The interesting thing I've noticed is that all the Irem stuff I seem to be getting have very similar (in fact virtually identical) PCBs. It's like Irem put out all their good stuff on one PCB format. It's almost spooky. I know that X-Multiply and probably Gunforce 2 also share this PCB. Since virtually everything that comes out from Irem is good...my question is a simple one.
What should I get to complete the collection? What other Irem PCBs are "must-haves"? I've already got X-Multiply in my list, along with Image Fight (which I've not even SEEN for sale). Are there other serious must-haves for the 'Irem collection'?
Oh...and a side note...was Image Fight 2 ever released in PCB format ANYWHERE?
EDIT: Just picked up X-Multiply too. It seems to be a bitch to find so I didn't mind paying a fair bit for it....
The must have Irem PCB list -
R-Type
R-Type II
R-Type Leo
X-Multiply
Cosmic Cop
Fire Barrel
In The Hunt
Dragon Breed
Ninja Spirit
Mr. Heli
Image Fight