Hello & welcome, looks nice and a clean example,
Starting off at the back box is a good idea at least that way you won't waste any money and you can work further down the sections to get the volume to your taste,
I've briefly looked at the link. Looks good and I'm sure some of the members here have used them,
One thing to consider is the diameter of the middle section it's joining to if it will be a straight swop with no modifications to fit ?and 2nd do they do a centre scetion you want to change that in the future ? May as well get a system that does both bits then there will be less hassle when you decide to change the middle :-D
Have a look at the centre section on your car see how many resonators it may have, if it's more than one it will be fairly quiet until you give it the beans
One of our members has just changed his prodrive back box for a ninja one from scoobyworld and has posted a vid. There stuffs top quality but costs a little more,
Dump valves are personal taste, the stock one works well, some people report lumpy running when aftermarket ones have been used without remapping, others dont have a problem.
Again with filters some eat through maf's and some people say they have had no problems,
If you were thinking about a new one go for a 'dry' type to lessen the chances of killing the maf.
I'm sure you probably know this but always allow the car to warm up before driving hard and cool down for a minute or two, although our turbos are watercooled and shouldnt need to worry about coking up it doesn't hurt