Good analysis. I use 13's daily and really like them. I own a 250xp with lift cylinder and would take a 13. The 13 is gonna feed so much better than the 290. The 15" capacity will make a big difference too, and the 13 doesn't have a problem chipping that size material. Doing mostly manual/bucket work, you are going to wanna load the feed tray and chip only when you have a good amount of material to chip. Having a chipper run at full throttle and only throw a few branches in at a time is a waste of money concerning fuel. Staging brush and only chipping when needed is the way the way to go. Start a few branches and then just load the feed tray; the 13 will pull everything in really well and you wouldn't have to have the chipper running at full throttle very often.
The only downfall is I believe that 13 doesn't have dual feed rollers, so it may be a pain to chip certain material. Overall, I think the extra money is well worth it.
