I have never tried the thin swiss from BA but i have recieved a very durable Swiss lace from another internet company and i have to say that in over 7 months i have never experienced any fraying which is a godsend,especially where Swiss lace is concerned!!
I doubt this is the same lace that BA uses though as,like Tim says,some people are saying that BAs lace does fray.
I have to say that all Swiss lace pieces i have ever recieved from other companies,including here at Toplace,will almost certainly disappear if attatched properly.
The durability is the main issue with Swiss and maybe John could look at what options are available for him regarding that lace i mentioned.