Hi all just wondering if any one can help me as to what exhaust would be the best for my car and what I want from it

I have growler intake
Underdtive pulley kit
Flashtune
Hi flow cats and hm headers

Im also wondering if any one does a quad twin system for the ba xr8 utes,
I'm looking for a reall good v8 note, a deep note and want it to be on the loud side even on idle
I' can't seem to find any quad systems but been looking at difillipo big boy system, manta system with hot dogs in midle etc.
Just after a good sounding good brand stainless steel exhaust that will also add some power but more after a loud noise

Well, depends again on your finances.

If you want, you can buy Difilippo and get a very good exhaust system for your ute but keep in mind that his gear costs more than anyone else's.
You could also consider Manta gear as it seems to have a decent word of mouth rep.
Pacemaker have been around for a long time and they have whole systems to suit your ute as well as being cheaper.
Otherwise, you can get someone to custom make you a full system to your requirements and probably get it done for cheaper.

I guess it really depends on your wallet.