So I reached out to Storm Lake about using that barrel in the 2.0 compact. The only response I recieved was a blunt
"No we do not have a barrel that will work in the compact 2.0 smith."
Also after looking at specs for threaded barrels centerfire are generally threaded for a length of 0.60" and rimfire for 0.40". So assuming a barrel length of 4.28" that means either the threads do not clear the slide itself or the barrel length is measured to the start of the threads and will have 0.28" protruding before the threads start, probably affecting the cycling.
I also reached out to Apex, they make a 4.0" that was released 2 days ago but nothing mentioned yet for a threaded barrel. I assume they will make one but time will tell. I am told the tolerances between the 1.0 and 2.0 are slight and may require additional fitting compared to the 1.0. I also asked about using a 4.25" 2.0 barrel in the compact and I was told it would not work due to lock up issues.
As of right now the only company I see making a longer/threaded barrel specifically for the m&p 2.0 compact is blacklistind.com.
Will you guys bring in barrels specifically for the compact when available?
I am a little leary as to using a barrel not designed for the 2.0 compact.
I would hate to buy these 2 items only to have a gun that malfunctions all the time when firing or worse isnt safe to fire.