Which nitrous kit?

I will be controlling timing with Fitech, it is the power adder series so it has many features in regards to nitrous. I bought it through pace, I plan on buying the nos setup through him for the customer support. He gave me a couple choices on kits, I was just checking if anyone had preferences on certain setups or not but it seems to be very basic . The reason I asked about the purge valve is I'm trying to keep things concealed as much as I can, I have a shaker on my car, hopefully I can hide everything and the more components the harder it is.