This thread is a little stale, but I thought I'd add my .02
For me, making furniture, here are my requirements in order of importance:
I recently needed a new jointer when the 37-190 of 15 years died. I called around and found a PM 60 used for really cheap. I had decided that I needed an 8" jointer in the worst way since thats what everyone said. I went to the store, cash and straight edge in hand and was very disapointed when I found the beds to be warped. This place had several 8" jointers, new and used in stock so I decided to look around.
I sampled at least 5 jointers, and found EVERY SINGLE bed to need work. Very discouraged to say the least. So I opened up my requirements and finally found a PM54HH (6" powermatic with helical head) that was dead flat. Bought it on the spot. I told the saleman that I wanted this jointer, his reply was, "OK, let me see if I have any in stock", to which I replied, no, I want THIS jointer.
So, yes, I settled for 6" jointer with a helical head, but I knew it was dead flat.
Best decision I've made in a while. It's probably the best tool in my workshop that doesn't say Clifton or Lie Neilson and I've never regretted not having the extra 2 inches.
I guess the bottom line is, make sure you understand what the tool is supposed to do and make your decision based on how well it will perform that particular function. There are a LOT of jointers out there that don't actually do what they are supposed to do, despite the technical specs.
Just my opinion.
Alot of us suffer from "Bigger is Better" Syndrome.