He may need a 4 row, I had an A630 on my M2 and 180+ bu corn and it couldn't run slow enough without throwing corn out the back here in IA. I ended up looking for an l2_3 and got an N series to solve the problem. The M2 is a Great machine but in high yield corn, 630 heads are not good from my experience.
I don't know if it helps either of you two but I have one I'll take best offer for it. I live in Northeastern OH. The only thing it needs is the ends to four of the snapping rolls and other than that it seems to be pretty solid, I never used it to havest but I know that it is not froze up. email me or post me a message if your interested.