I looked closely into getting a pair of these and very nearly bought a set, but in the end went for a Holan setup which just seemed to tick more boxes for me (no pun intended!)

My decision was made on the basis that: (1) The OTR boxes are bare aluminium, so would need lining or bags using or everything gets covered in black oxide dust (Holans are powder coated). (2) The attachment and release mechanism is a bit Heath Robinson having to insert a long steel rod and fixing it under the catch (it's going to get bent/lost and it's fiddly). (3) Whilst strong, the OTR frames (IMHO) look a bit sh!t when the boxes aren't fitted. (4) To get the same volume as Holan panniers you need to have a much wider box (wider than the handlebars) as all three sizes aren't very tall, so capacity has to be made up by width. (5) Cost.

See here.

In answer to your question about crash damage, the OTR panniers are very unlikely to detach in an accident. I would say that the boxes would just crumple and bend as they are the weakest link. The frames and mounts are strong.

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