i found a gen 2 m frame a few months ago on eBay. I was at a Vault last week and picked up a set of sweep lenses. When I installed them, the fit was pretty snug, but they eventually popped in. But then I looked closely and the lens had created 2 cracks in the frame. Did oakley change the lens fit between 1997 and the pre-M2 frames, and did I then force the lens into a frame it wasn't designed for, or did I just have a really brittle frame?