I have the rMB. They are phenomenal... for their size. They're not better than the current 15" MBP speakers. At least to my ears. But, they are better than the 13". So they should be an upgrade but don't expect miracles.
Lol ive been trying to sell my 15in macbook pro retina late 2013 for the past 2 months with no serious offers (been selling for around 1k-1.2k). Today, I messaged a guy on craigslist about trading my macbook pro 15in 2.0gdz for his 2015 12in macbook 1.1gdz. Do you guys think this is a good trade for me? I believe the stuff I do will suffice on a 2016 m3 macbook (i dont do any video editing, etc), but is the 2015 1.1 model that much slower? im going to miss the 1 hour extra battery life. What do you guys think? Or should I wait till the new 2016 13in macbook comes out and get a more well rounded computer?