It sounds like I'll be looking for a SWD until an Ingram becomes available. I was hoping to find one before the .223 upper is announced for them. The only problem with that is any upper designed for use with the SWD magwell won't work with the Ingram Mac if I find one later.
There will no problem using a M-11 or M11-A1 lower receiver made by PS, RPB, or SWD with the Lage MAX 11-15. All the OEM .380 uppers should also interchange without issue.
The large magwell allows you to run the Lage MAX-11A in 9mm. It also allows the use of the 9mm CF-W slowfire bolt. Though not produced recently, the Lage .22 conversion can be shortened to function in the small frame M-11 with a large magwell. These are the options that open up to a large magwell gun.
All other uppers will fit and function without regard to the magwell size.
Most, but now all, SWD M11-A1 lower receives share the same magwell and mags as the M-11/9. Sam at Practical Solutiions offers a service to replace a small magwell with the larger version if that’s a requirement.