1. Sound quality
This difference in the KH 4222, for he is compared to others without volume and very much treble. All other models sounded the same and good though. The SHB 9100 has thereby certainly most bass, the SHB 7000 and KH 4223 sounded the most balanced.
2. Connection / Connectivity
The Bluetooth connection was 4222 significant dropouts when KH -> exclusion criterion. In our 60m² apartment with many WLAN and Bluetooth connections I have not experienced a single misfire at SHB 9100. Class!
The SHB 7000 and KH 4223 settled despite many attempts and tricks NOT connect with Windows 7 (64bit) -> exclusion criterion!
3. Processing / fit
The two Philips models had generally a tighter fit than that of AEG, which I felt as not optimal. From the comfort me only the SHB 7000 fully confident that start at his ears even after 1 hour listening to music does not glow. Ultimately, the taste will be, but I have found that my "on-ear models" are too warm. There was no noise disturbance by / from my glasses. When SHB 7000 Unfortunately the plastic of my glasses when quitscht Mitnicken to music with the imitation leather the headphone shell - a shortcoming so the circumaural design for eyeglass wearers. probably the price is still too low to use higher quality materials here: shame! The KH 4222 was the easiest and certainly the most portable - the SHB 7000 the heaviest and not to shrink the only. Highest quality appeared in descending order (equivalent weight): SHB 7000 SHB 9100, KH 4223, KH 4222nd
I hope I can help you a bit, so you do not have to all models even ordered.