Not going to see much, if any difference between a 48/42 .36 and 52/42.46. Slightly more aggressive in the bottom part of the shift.
Stock secondary black/purple is 160-240 , which in my opinion is too stiff for the helix they use. The stock spring would probably be better with a full progressive or something like 58-44 .46. Cheapest change would be swap for a softer secondary spring( 140-220,155-222 or maybe a 140-200) and use the stock helix. Will be trying run some break in miles on mine today(brand new 15 600 pro-s) , don't think much difference between our sleds (basically identical as far as clutching , gearing and engine). I trying a 140-200 today(stock helix) and will be switching back to a 140-220 or possibly stock spring with a new custom progressive helix when in comes in Tuesday.
Friend also bought new left over 16 pro-s 600 and has his is past the break in ( about 450 miles). He is seeing 8350rpm on eth setting, and 8450-8500 on 91 non-eth setting(bone stock). Which is at least 200 too much. Haven't seen a dyno sheet on these newer 600 engines yet, but my 06 fuse 600 ho ran best when clutched to run 8150 and creep up to 8200-8250 on a long run.