Diff between Apexi N1 and Apexi WS

[atehrani]

What is the difference between the Apexi N1 exhaust and the Apexi WS exhaust?

If you had the choice, which would go with? Either Apexi or TRD and why?

[Spec GTS]

all i can think of is that the style of the canisters r different and i think the ws exhaust is less quieter than the n1. their website has more info on them http://www.apexi-usa.com/exhausts.asp