I think all racks spoil the looks of the XTs. My choice of luggage is the Oxford Lifetime Expander Sports Humpback (28ltrs)which can be tank/tail/rucksack as required. I place a shaped piece of felt carpet underlay on the plastics.
For my monthly visit to the shops in Spain I add the matching throw over panniers (65ltrs). No burn problems on CCC carbon exhausts.
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