well if you want to hit some trails or live in a hilly area and will use the bike to commute, get a specialized, if you just want to ride stree/park/dirt jumps get the black market. it really just comes down to whether or not you want gears.
Depends on what your gonna be doing. if you ride street, the specialized bikes wont be as good. they have a low bottom bracket height, so it wont really feel as poppy, and the head angle is such that the handleing will be poor at low speeds, but this all makes it great for park and dj's.
gears are gay. chain slap sucks. i swapped from a 9-2 setup to SS and loved it. My rear cog is too big so i'm topping out way too easily but a little fiddling with ratios will fix that. its lighter, simpler and less expensive and with the right SS setup you can still get around very easily.
SO why would you go for either of those? get the p.1 if you plan to SS it. Same thing as the p.2 chromo but less money and it comes the way you'll need it.
Personally I would say go with the Blck Mrkt three 57 . Its a solid bike thats all you need, it will dirt jump and rule for street. No offense to specialized bikes but they're a little heavy.
Not to mention on the chromo bikes specialized makes allot of the parts suck and fall apart anyways.