2.5 vs 3in

My 2012 tdi is deleted and has a half tune for mpg. I want to do a muffler delete to a straight pipe. The kit that was put on used parts of stock exhaust and was wondering if there is a big difference in sound with 2.5 and 3inch from turbo back. I cant find any videos with 2.5 fully straight piped on the mk6 tdi. Any info would be awesome!