ZZP DP on N/A: 2.5" or 3"?

[SlowNA06]

It looks like a lot of guys here are 3" fans, but I just wanted to double check, since the ZZP site says that I ought to go with 2.5" for my NA 3800... I'm just not cool like all you GT and GTP cats, so I wanted to make sure I'm no special case. I'm being bad and trying to stay away from a tune until I've figured out how I ought to go about it for my '06. So... if you see anything you know would make me throw codes, feel free to speak up!

Grocery list:
ZZP PLOGS
ZZP Downpipe + cat
180* Tstat
9" K&N cone short ram intake

Might be a cam or rockers... or rockers and a cam in my future. But at least not for a good while. Would this influence the choice? What do you guys think?

 

[CTKGP09]

Grocery list:
ZZP PLOGS - all you need is the front one, the back manifold isnt as restrictive
ZZP Downpipe + cat - get the 3'' theres no need for a 2.5'' unless its your ONLY mod
180* Tstat
9" K&N cone short ram intake - make sure its 4'' in diameter

if you do that id say money well spent

 

[Warbeaver]

ive got a 3" ZZP