LBA (low band apply) applies the rear band along with the sprag (low roller clutch) to help hold the rear drum. If the sprag lets loose the forward drum can go to 14,000+rpm. I have used both. I like the old style non LBA better as the 1/2 shift is cleaner. I would recommend a good aftermarket front drum either way. I've run both aluminum and aftermarket steel front drums. My preference is for the lighter aluminum piece. For me wear on the aluminum drum has been a non issue as well. Top shelf doesn't necessarily mean stronger. More like lighter and quicker.
Doug