I tried the Martin FX on my 1930 Martin 2-17 but ultimately switched to DR Sunbeam 11's, which are round core strings and, like Martin FX, have reduced string tension(regular light strings caused the belly to bow on the little 2-17 significantly). I just find the Sunbeams give me richer tone; DR calls "11's" medium-light and "12's" medium, BTW. Might be worth a try for you for something different. Not often available in stores; check Just Strings or similar internet companies for info and pricing.
I've been a big fan of JP strings and use PB lights on most of my guitars. They're the house brand for Froggy Bottom Guitars (80-20's on all, including mine). Since I carry a Medicare card it might be that I'm not hearing the loudness of the JP's; I have had complaints that I play too loud on occasion (I play primarily fingerstyle).