Most any review you will read between the V1 and the Passport 8500 will put them in a near tie, or give one an advantage. Out of them, I'd choose the V1. It's a tad more 'spensive (IIRC) but the aarows feature is nice. Some will say it's useless but the passport has modes that are equally useles as well (I.e. the frequency display, who cares what Mhz the X band you're being tagged with is coming in on...)
I'd personally NEVER run a cordless. Newer models claim that batter life doesn't shorten detection sensitivity and distance, but I believe that's BS.