Hi, Tony, I think B&W would say that the htm2 d3 is the better match for the 804d3 since the drivers would be the same size. While I haven't heard the new htm2, at least one other person on this forum has the same set up (804 d3 and htm2 d3), and he seems to be pleased with the combo
.. I definitely would recommend one of the new d3 center channels so as to match the timbre of the 804s. Since the htm1 drivers are larger than that of the 804s I think it might be a mismatch. I can say that the bass and midrange are much improved on the d3 speakers in general, so I doubt you would be disappointed by the changes. Perhaps others here can chime in their thoughts. I can only tell you that the htm1 is the recommended center for the 802/800, and with my 802s it is a great match. While my htmd2 sounded okay with the nee 802d3, having a d3 center has made the front soundfield so much better. The timbres match very closely (although an exact timbre match would be if I had another 802 for center, but I didn't have either the funds nor room for that!), and the new center matches the speed and lower distortion of the new mains, allowing my 802's to better be heard for the great speakers they are.