I dont want to sound like an ass here but.........
You get what you pay for and I have learned a lot of lessons over the years dealing with hopping up a car. Dont cut corners, especially on a turbo application. Go with a custom or turbonetics manifold. This is serious stuff your dealing with and dont let some shmuck butcher your car. Plus one you want to resell it what mani are you gonna use? You are going to have to buy a new one from mazda....and I bet its way more than 500 bucks!
There are alway hidden costs when dealing with a custom install.
You think to yourself hey. I get a turbo, some charge piping an intercooler, fuel pump and I am done. But it does not work that way. A lot of thought and ingenuity goes into a sytem. Currently I am experiencing some small stuff with my turbo. I will redesighn it over and over until the whole thing is a perfect package. Unfortunatly this takes some time but thats what research and development is. When it is bug free I will release a kit.
I am not telling anyone to buy my kit or joe shmoes kit but a turbo takes alot of work and there are always hidden costs. You need oil lines, clamps, silicone hosing, new diaphrams for your map sensor, connectors blah blah blah. You guys get the point. But if your willing to put up with all the costs and b.s. more power to ya!! I would love to see more turbo mp3's on the road and going custom is a pain in the ass but its kinda fun
Just remeber these important rules
DONT CUT CORNERS
Keep that thought in mind and you will have a rewarding and killer turbo system