If you are talking about riding only into the forties, then shoe covers are the way to go, maybe adding chemical warmers. If you are planning on daily riding in the twenty to 32F range, winter boots make more sense. IF YOU BUY BOOTS, TYPICALLY YOU NEED 2 OR 3 FULL SIZES LARGER THAN YOUR REGULAR SHOES. That is to allow room for 2 layers of wool socks, and you must not have any pinching. Any restriction of circulation to your feet will mean that you will have cold feet no matter how well insulated the boot is. So if you wear a 37, you should probably start with trying a 39. Be sure to take the socks you will be wearing with you. Look for boots that will completely cover your ankles, that allows a better air seal between tights and boots, keeping you warmer.