With the 640p, there are quite a few DIY upgrades on the internet. The same very well could be true for the 651. Depending on your comfort level with component soldering, it would be yet another hobby. i haven't moded my 640p yet.. But, likely will in the not too terribly distant future, once i get all the projects around the house caught up...
When i was in the market Cambridge seemed to be a very good value, which is why i went that route. Good luck, and let us know what you get and what you think of it when it arrives.
