I have some smarty cargos and I love them. Super toasty with the liner in (make sure it comes with the liner!) and nice without it on bluebird days. As others have said they do run a little big. I normally wear a size large but got a medium and they're still bit bagy, which is nice though if you ever wear ass pads. I'd said if you normally wear a medium a small is fine but if your sometimes between a medium and a large then the smalls probably won't cut it. Also are you looking at geartrade by any chance ? If so make sure you ask them about the liner b4 you buy.