Based on what I read on british forums, some have found the Dentons to be richer in tones and details compared to the 220s.
I really like the Dentons personally. They are very pleasant to listen to, sound good at low volumes, image very well, never bright and harsh, on the warm side, and from the pictures I have seen, they are made with wharfedale drivers, and quality crossovers and binding posts. Internal wires are particularly thick.
The cabinets are exceptional at the price point. I just compared my dentons to a pair of kef Q100; while the KEF are fast and offer a bit more details and air, they are not as refined, natural nor musical.
Wharfedale intented with the dentons to bring back the old wharfedale sound to music lovers - It is an 80th anniversary version and they were conceived with special care. The 225s are probably more generic.
The dentons are not monsters of details nor super dynamic, so if you're looking for a warm, lush sound, they are for you. They require good amplification, in fact I do not believe my marantz integrated 8400 is a good enough match. I hope you can listen to both - beware of the dentons running time, they need at least 100hrs before developing and be more balanced. have fun
