Mike, I actually feel the opposite of how you feel about the Sebo Felix. It's one vacuum I have grown to dislike!
It's VERY top heavy, and puts out a lot of hot air while vacuuming floors or carpets. So much so that I won't use it in the summer months from May to September. The swivel neck on the powerhead doesn't allow the ET-1 powerhead to swivel much at all - why they designed it that way is beyond me. Hair and carpet fibres wrap around the brushroll way too easily and need to be cut away often. And I also found out with use the ET-1 powerhead doesn't work well with certain low pile area rugs or carpeting. On my rugs, position 1 is too low, yet position 2 makes the brushroll just skim over the rug. The Sebo ET350 powerhead is MUCH BETTER than the ET-1, cleans just as well and doesn't have these problems. So much so, I am replacing it with the ET350 and putting the ET-1 powerhead up on Ebay!
The bags clog easily - I have to take the HEPA Cloth bag out, put the cap on and vigorously shake the bag to loosen dust from the walls of the bag 3 to 4 times while filling a bag so the vacuum has full suction to clean properly. The S Class Filtration system is also a joke - watch Performance Reviews compare a E3 to the Miele C3 Brilliant with a HEPA Filter installed and the Sebos is SO BAD at filtering, it's just as bad as a Miele using the genuine Super Air Clean filter on the exhuast! The hose is awkward to get in and out of it's holder, and it's short - you either have to have 1 hand on the vacuum at all times, or use the optional extention hose. The Kombi Head available for the Felix has the brush extend/retract pedals awkwardly placed, and both it and the Parquet Brush don't swivel well and won't stand up on their own.
Whoever the idiot German designer was that designed this thing ought to be shot! I would NEVER recommend anyone buy it or the Sebo Dart! My Shark Rotator NV501 is much easier and enjoyable to use, cleans just as well and filters much better. Yes, you did just see someone here recommend a Shark vacuum over a Sebo!