The roof over the car is the important item for protecting the car (hail). Having sides on the car port to make it a 'garage' are more of a cleanliness and safety (theft) advantage. As long as you're not a clean freak or live in the hood I don't see any issue with a car port.
Besides, you could always close it in for a few hundred bucks in lumber and siding if you decide a year from now that is needed.
2006 Lotus Exige: Avery Matte Graphite wrap, partial built motor (9:1 Mahle pistons, Ferrea Competition valves, ACT Clutch, ARP head studs), REV400, Nitron SAs, BOE QS exhaust, Ultradisc rotors, Moroso Oil pan, Circuitworks oil pump, CF Stuff (Cup Roof, ReVerie diffusor, side scoops, APR air dam, craftsquare mirrors), Worksbell quick release, Odyssey PC625, Morimoto Xenon HID, BOE Rear Oil Cooler, Difflow Aeroplates, BOE Swirl Pot, DaviesCraig EWP, Reversed Heater Matrix