2006-2012 audi s3 stage 1 remap + milltek non resonated - local to Worthing

Stage 1 significantly improves drivability in the S3, so no need to worry about that. The addition of an exhaust, cat back I assume rather than TBE as you are not going Stage 2 will make little difference other than noise.

If you are really worried about noise consider a resonated Milltek which later could be easily converted to non resonated and the resonated section sold on if it was too quiet. It depends what you consider loud really! I think you'll struggle to find a S3 running stage 1 with a cat back as most S3 drivers stay stage 1 on standard exhaust or go TBE and stage 2/2+.