We've done it several times and we just got back. We wouldn't do it any other way. We had our van break down one time (luckily) just outside of a dealership in Fl and that was a waste of a day to get it fixed, as well as the cost in USD! After that, we've always rented. I figure the cost of the rental is about or even less than the cost of the upkeep on our vehicle. Besides that, we get a new GC van to drive and don't have to worry about space or breakdowns. Even if we do have a problem, we call the rental company instead of a towing company.
Now, I use Costco travel to book my rentals because I get the free extra driver and the 2% cashback for being an executive member. In my case, while it would be closer to rent from a local location, we booked our rental out of YYZ, which is a half hour drive away for us. The savings were well worth it. Also, I found my best price for my rental somewhere between 2 and 4 weeks before our trip. Enterprise gave us a brand new van. When he heard we were taking it into the US, he made sure it had low mileage, so we wouldn't have any problems. It was unlimited mileage (not all agents offer that, you have to look around) and it was roughly $27/day over March break. I was told I got a lucky deal, but even if I'd paid double that, it would have been better than racking up miles on my van.