I got a Surly CrossCheck so I could use it for everything; commuting, errands, long rides, even smooth trails as-is, or just-a-little-rocky trails if I swap to 50mm tires (but I have a hardtail MTB I would ride on trails typically). Sometimes for a really long ride (for me >20mi) I will take the rack and lights off. About 30sec to get them off, about 2min to get them back on and I'm ready for commuting again.