I'd say they fit pretty true to size. I would be wary of sizing up in them, since they are usually suede and that stretches out. Also, the drop-in insole is that UltraCush 3D insole, which is made out of EVA instead of the normal UltraCush HD which is polyurethane... the EVA is heat moldable, so it will crush out and give more volume over time as well. Basically, if you get it in the correct size, it will mold to your feet after awhile.