Thanks for the advice everyone!!
In reply to you Piris, right now I'd rather have a fast Cento and cheers btw for all the info, its really helpful.
Right now, and for the next few months my budget's pretty low so I cant afford any big modifications just yet. If it doesnt effect my insurance too much (I will have to check) I would love to get a back box and probably for the moment just an ITG filter for the standard air box.
Also can you explain what you mean by drilling the airbox? literally drilling holes around the edge of the box?
I was considering an APEX kit for £80 but I will be looking for an alternative, what would be a good kit to aim for that I might actually be able to afford?
Cheers,
Ben