You won't like switching from a 688 to a Deere of any model. The greens are simply not the baler as the old 688s were. I can roll into a heavy field faster and make more uniform, heavier bales than any JD that I've had to bale beside. The new BR780s are ok, however the external greasable bearings on the rollers are not all they're hyped up to be. You may not blow as many bearings, however when you do lose one, you often take the stub shaft out of the roller as well. I know many custom guys who wished they'd stuck with their 688s instead of upgrading. For the casual baler, less than a thousand bales a year, the BR780s are just fine though.
Another thing to look at is a Hesston 956/956A or the Massey equivalent. I had the opportunity to bale beside one last year, and their pickups are simply second to none. I had my NH pickup set as good as I could get on a light windrow, and I was leaving behind a few sticks. The 956 I was baling beside wasn't leaving anything behind at all. They appear to have slightly higher pickup RPM, not to mention a much heavier pickup than either the NH or the Deere. Overall, the entire machine is built heavier than either a NH or a Deere. The brand spanking new 956s utilize 2 bearings per roller side (total of 4 bearings per roller), which I think is a better option than the external grease types. I talked to a custom baler who had switched and he'd done 20,000 bales without losing a single bearing.
As a side note, I work at a Massey dealer doing parts these days. We sell bearings and teeth for all makes and models since we're the only dealership for 60 miles, and I brought in several sets of bearings for the 956s (including the earlier model ones with only one set of bearings per roller) and I sold two lousy bearings to a first model year 956 with 14,000 bales on it. I think thats impressive. Whether I continue to work at the Massey dealer or not, my next baler is going to be a 956, probably the the A model with the self contained hydraulics and the auto-everything. Very nice in cab monitor, better than the Deere or the NH by far.
Its another option to think about. Having said all that, there are plenty of low bale 688s around that sell cheap these days.
Rod