Going to have to disagree with you on the frame. a solid frame will always be far superior to a frame with removable sections. The issue with cracking that some XP owners have had is proof of that. call it abuse, call it neglect, either way, the frame cracked which is not an issue with the VL frames.I prefer the sound of the 570 and the trottle responce isn't a world apart. The 570 is maybe a little snapier but nothing to write home about.More advanced in regards to chassis? I think the 570 has the more advanced motor. Did they feel similar in throttle response?I shopped for one last week. there is a 1200$ difference canadian between the 550 and 570. after a small ride on the 570 in the parking lot and a lot of thinking, I rather pay the extra and get the 550. Both bike are great but my riding style is fitted better by the more Advanced 550.
The 550 motor sounds like a diesel engine (sounds like there is a handfull of quaters loose in the top end, rattles), the 570 is nicer.
EPS is the same.
Yes the 550 is more refined, better ergos, suspention, frame, ebs. steering is a bit more precise. Racks are better on the 570 but the whole atv looks cheap compared to the xp. I don't know if the 14 in weels make a different in handling but the atv takes curves and sharp turns better.