I'm surprised there isn't more May car rental chatter yet. I guess I will give this a bump and see if anyone had found anything good. The best price I am seeing right now is booking through my Visa rewards points. I could get a STD car for 10 days for $230 with Alamo. The best part is that is in Canadian. Exchange is terrible right now, so paying in Cdn helps. I can't find anything that low in USD anyway. Once I use my $90 in Visa points I would pay $140 for the rental.
My only hesitation is that after renting cars in orlando for years, I know better than to prepay. A better rate usually comes along. Then again, car rentals haven't seemed to follow their typical patterns on our last couple of trips, and our exchange rate is so bad right now that I'm probably better off to take what I can live with. However, we're still four months out at this point.