Direct Port Nitrous

Hey guys now before everyone starts telling me the horror stories dealing with nitrous. Ive looked on here and kinda read most of them. I want to know what you guys think of the noszle direct port system. I think holley or whatever has it on their website. My buddy and i were looking at it and he was trying to get me to do that system. Im thinking of doing either a 100 shot or 125 ( if my motor can take it). I do plan on getting a tune. I want to know do i need to upgrade my fuel pump. What about a fuel pressure regulator? Also if my stock bottom end can't take the 125shot. What kinda cost am i looking at to get something stronger?? Basically i want to run a 150 shot reliably. Thats my main goal. I want to know what the cost would be to do that and what do i need to upgrade. People who have already done that please chime in here.

Now the second part : With the system im going with a WOT switch rather than a push button. I want to know a couple of things that ive read are true or not. Do i spray in first or no? ive read no. I have 4.10's in my car. Im thinking i would have to launch in 1st gear. Go to second and activate the nitrous. I usually powershift ( don't let off the gas ) <-- don't know what everyone else calls it. With nitrous activated would i still be able to do that?

Thanks for the help i know its long but i just wanna know to get it off my head.

Eventually after i build the motor i want to go higher in the shot range. Im going to start off at a 100 and go from there. Definetly going with the direct port system though. I feel that its much safer. So most of u guys suggest to upgrade fuel pump and get some kinda fpr? Also what kind of tires do u guys recommend to hook. I have 245 nitto's on it right now and they don't hook for crap. If i need to go bigger what size and what kind of drag radial. The car isn't daily driven so i don't care about tread wear. Just want something that hooks.