A few years back I had a discussion with the Pelican people about the likelyhood of a box cracking at a drilled hole. They basically agreed with my assesment that it would not crack, although obviously they need to protect themselves in the event it did happen. The plastic is very soft which is excellent for not cracking, that combined with the feature of those little pockets with thicker material around them, it's like they were meant to be drilled. I would rather drill and take my chance than have 40 lbs of framework surrounding the pannier. As a further precaution you can do what I used to do,....use 1" fender washers, with 1" rubber washers underneath on the inside of box,....on the outside of box, custom cut a thick rubber washer to fit in that recessed area and then a plastic spacer. The whole surface is surrounded by rubber, very little weight hanging on the bolt holes this way. I usually used 1/4" or 6mm fasteners for these. If you attach lid to rack, instead of main compartment, you have just created a hard to use pannier. In fact one really nice feature of a Pelican box is that the lid is shallow, so gear can stay relatively in place when the lid is opened. Even Original factory luggage has the useless feature of opening clamshell style in the middle. OEM luggage is also thinner and cracks easy compared to Pelican. So it is a worthy project to mount Pelican boxes, if one ever did crack as a result of a crash, the $70 Pelican is still cheaper than buying a replacement Aluminum pannier. If Pelican made that 1420 in a larger size it would be superior to Aluminum luggage in almost every way.