Gee Light, I use the NanoWebs and they sound better and stay in tune better than anything else I've ever had on my Martins.
I used Guild 80/20 Phosper/Bronze for years until they moved production to Mexico. I gave up on Martin Marquis, after buying them by the carton for years, when I started getting LOTS of low-E duds.
I've tried Pearse, D'Addarios, probably all of the major acoustic strings. I guess I've used the Elixers exclusively for about the last 5-6 years.
I agree the PolyWeb's sound dull. But the Nano's give me enough of the deep tones I like without being TOO bright.
I use mediums on my D-35L, and lights on my D-45L.