I've owned the CDM 1SE for about 11 years but have not listened to the CDM 1NT. Both are fairly good speakers during their time but are sadly eclipsed by newest and latest models available in the market today(not those from B&W). The trickle-down Nautilus tweeter of the CDM 1NT is said to offer slightly more refinement and detail than the 1SE. If you are still looking at these two models I would pick the 1NT.
Good luck.
Good luck.