I'm looking to upgrade my exhaust system to something that will give me a little more HP along with a more aggressive sound, I'm trying to keep the cost under control because I would also like to have my ECU re-flashed to either stage 1 or 2.
As of now I'm looking at AFE, Infidia or even Borla (this companies prices would be pushing the amount I would like to spend), I'm working with a budget of around $1,300.

 

On my 08 MCS I added the JCW factory muffler and I loved the sound - look into that and i think you can get one for a lot less than $1300. Found mine on the forums here for around 350 and got it installed for $100 at the local mini dealer

 

The $1,300 is for a exhaust system and a stage 1 flash of the ECU, but thanks for the heads up on the JWC exhaust.

 

I personally use and recommend the Akrapovic, but it is out of the budget range you had.

2nd I would recommend the Quicksilver as it's really cost effective and fits great with carbon tips. Also much lighter and still a full exh rather than just a muffler like the Borla or others.
https://www.waymotorworks.com/quicks...7-r58-r59.html

3rd would be Invidia still a full exhaust, not as nice fit as those, but does fit pretty good for the price.
https://www.waymotorworks.com/invidi...haust-r56.html

We can also do the tune for you.
https://www.waymotorworks.com/manic-...-cooper-s.html

 

I would start with a tune. if you go stage 2 and catless, it is a good bump in sound. I personally like the sound of a stock exhaust with catless downpipe.
From there you can decide if you want an catback. Plus a stage 2 tune plus downpipe and FMIC, can easily exceed $1300. (i went the budget route, which i am happy with and that was $1000+/-)
JMHO

 

 

 

Assuming you're either in Clark or Washoe co and the smog is really just an OBD2 read for gas powered cars. If no active codes, it passes. Never had problems with the R53 which had a Dinan S1 package (exhaust, intake, tune) in Washoe.
Totally different story for diesels as they need OBD2 read plus underhood inspection for stock parts plus sniff test on dyno. That and there's only one place that does it for AWD cars in the whole county. Sorry, off soap box now...

 

No problem, we do same day turn around on the ECU so if you want to overnight it we will ship it back out the same day we get it to minimize your down time.

 

I have a quicksilver exhaust with a catless CNT downpipe with the RPM Stage 2 tune. Love it

 

Here is an exhaust clip of it.

 

I skimmed through the replies and didn't see this point brought up: Replacing the downpipe with a high-flow with cat or catless will give you the best potential for power when you go to tune. The rest of the exhaust behind the downpipe is relatively unrestricted in the MCS so upgrading that won't change your power (unless you're doing a serious build) but will definitely give you a different sound. The stage 2 tune needs a FMIC, intake, and downpipe, so if you want a little more power AND a little more aggressive sound swap out the downpipe. I felt like I got the biggest jump in HP going from the stock FMIC to a higher flow Alta FMIC; the stock one is pretty restrictive. The only thing you might not be happy about is the FMIC won't give you any more of an aggressive tone. That being said, the bumps in power were pretty negligible from stock - I just sent my ECU off to get the RPM Stage 2 tune which seems like the biggest bang for your buck in terms of power.

Whatever route you go, good luck and have fun!