Nothing looks better than a dropped P5 on 17s, IMO. Thinking long-term, it's probably better to get the 17s now, maybe run tires with a little more "meat" on them, like 205/45s (that's the stock MSP setup) to reduce the appearance of gap. That should be a good compromise. Later on down the road, when they wear out, or when you do your suspension, you can opt for 40-series tires at that time.