I bought my 5 and was one of the first in Canada (and North America) to buy it. I've been waiting for this car for a long time - finally someone has the guts to bring a European-style Space Wagon to North America and do it right! This is a great little car. Don't call it a minivan, because it's not. It's a station wagon, or a hatchback. The one thing you need to realise about this car is that you can either carry 6 people OR you can carry 4 and lots of cargo. Engine-wise, it has lots of pep, more than enough for the car. It gets better gas mileage than any other 6- seat vehicle out there. It's also damn fun to drive, especially the 5-speed.
The 5-speed transmission is awesome and makes the car a lot more "fun to drive". It has incredibly good looks from the outside as well, and draws a lot of stares from people around town. The seats in the middle row travel back and forth as necessary and make it easy for 6 to sit in the car.
Off the top of my head, I can't think of anything huge that needs to be done to this car in the future. If I had one criticism it would be with the haphazard way that Mazda has released the vehicle. There are no accessories available. There's no option package in Canada - it's GS, GT or no 5.