I would say a Zex dry kit would be a good choice. Easy to install, you won't have to worry about fuel puddling in the intake, and can get very good performance gains.
Zex Ford kit (dry)
A purge would definitely help the "bling" factor, among helping to clear the main feed line for better launches. Plus I think the whole kit looks nice. Also a heater would help performance by keeping the bottle pressure at the right PSI, but according to their site the control box helps make running at low PSI safe....
It ranges from 75-125 shots, which any of those are "safe" with our engines.
A pressure gauge is definitely something you should get either way. Also an adjustable fuel pressure regulator would add to the looks, as well as help performance/safety. There is atleast 1 person running a Zex dry kit, and he produces really good times.
Nitrous Express definitely makes a good wet kit, gonna cost a little more though. You definitely would want a bottle heater, a window switch would be the best idea as well. It won't be as "fancy" looking as the Zex kit, but it doesn't look bad by any means. you will have the risk of fuel puddling, which a window switch helps prevent that. A bigger fuel pump is recommended, especially over a 75 shot.
There's a lot of variables and different options, so as more questions are brought up, they can be answered, other wise I would be typing all night