Stonemark is absolutely right. I have had of a brand new pair of boots come apart after a few river crossings and another time, got very bad shin bang from a pair of plastic mountaineering boots and almost couldn't walk out on a climbing trip where we'd flown in to the Upper Tasman glacier in NZ. I was miserable and it took a fair while to get better. You can cut corners on some things, but don't do it on footwear and make sure whatever you get fits before going very far in them.