CTF Outdoor is the largest field in the area bar none.
They have an excellent field with lots of diversity ranging from heavy woods, to open rolling hills which can make for some good play.
They have a large rental gun pool of over 200+ guns which means you can take all your friends out playing. Nobody else has that kind of numbers.
Staff is good, and willing to help you out with anything you need.
Free hotdogs and drinks are a nice plus.
The big games usually bring out large crowds of players.
Some of the downsides of this field
The fields in the past have been not so good, but in the last year they have made some great improvements in the fields. Huge efforts have been made to clean up and reorganize the fields and it really shows.
Prices are a bit on the high side for the once or twice a year player, but for those that don't know signup for a vet membership if you have your own gear and get cheaper paint.
CTF outdoor is my regular field and i'm glad that things have been shaping up to get better and better. With a little more effort I think they can become one of the best fields in Canada.