Does $8 difference for .357 Sig make a difference setting up a switch barrel?

Why $8 more for .357 Sig than .40 S&W in similar pistols?

FREX:
Smith & Wesson M&P Compact .357 Sig.
SKU: 109005
$727.00

Smith & Wesson M&P Compact .40 S&W
SKU: 109003
$719.00

Does this difference make a difference for a switch barrel pistol?

Which one to start from?

I gather Storm Lake barrels tend to run a little larger outside and may be less drop in (than S&W brand as well as a tad more money) - that is a tighter fit requiring more filing or stoning - but often or usually more accurate in a switch barrel pistol?

I've got a cart started at Brownell's with the Storm Lake barrels. Midway did have the S&W discounted for clearance to start this notion but Storm Lake isn't much more and I expect equal reliability and better accuracy from the Storm Lake if I do my part.

Ultimately planning to go all three cartridges (9x19 & .357 Sig and .40 S&W) with an RMR red dot sight on top - taking a cue from Gabe Suarez and Mr. Bowie on the red dot with the Crimson Trace for a backup sighting system. Some disparage the RMR - rightly - as lacking a backup system but I plan to live with that. Where it not for the red dot I might go with switch pistols instead of switch barrels but the red dot is too expensive to have multiples of pistol and sight.