Had it happen on my '94 (stock) Silverado about 8 years ago. I was lucky enough to be getting off the interstate right by my shop. Sure enough, the filter collapsed, but I was lucky to catch it in time. I called fram they sent me a form and wanted the filter back. I sold the truck and never sent them the filter and will never use another fram again.
I just use a Wix on my BBC and don't worry about it anymore.
Also make sure you use K&N oil for their air filters. No oil on the filter and you'll dust the motor if you drive in dusty conditions!!