Which sport quad for trails?

I've been reading a ton about sport quads and still cant make up my mind. I'm looking at a z400, raptor 700, or trx450. I will be doing a lot of trail riding but keep in mind I like to ride aggressively. My father in law rides a dirt bike on these trails and his GPS showed an average speed of 17 miles per hour on them. I want something that can come close to keeping up with a 2 stroke dirt bike in the trails but also will be reliable. I don't mind doing maintenance, I just don't want to constantly buy new parts because I don't have the money. So of those 3 which would be my best choice based on ability to haul ***, handle well in trails, and not be a constant money pit? Any help from people with experience with these quads would be great.

Z400

The Z is what I've really been leaning towards, I just don't want to get it and 2 months later want more power. I've heard they are easy to mod and make a lot faster. Is this true?

Have you considered a Honda 400EX? Parts are dirt cheap, the quads arent expensive, and they are stupid reliable. Also really easy to work on. They make great trail rides. Put a little money into the suspension and motor, and you will have a dead reliable quad that can tackle just about any trail and you can have some fun on the track as well. worried about getting bored with the speed? increase the bore size and you can get a lot of power out of them for the price and amount of money you spend. just sayin...

Just throwing this out there, have you considered 700xx?

Haha... 700xx definitely would.get the job done but they are expensive and I am not sure of the aftermarket (could be great for all I know...). But they are pretty heavy aren't they? Might get tiring IMHO... But I have never owned one... Just test rode a beat up one at a dealer (who still wanted $5k for it even tho it looked like it had been tossed in a meat grinder with gravel!). Power is definitely there tho.