If the MSW 1750 would work, you would keep that, but if not you will get PSW. Must be love of PSW--not logical :)
Note that a 1000w MW on PSW will want its full 1500w input, but only wants maybe 1200 on MSW and cooks a little slower. So if your MSW 1750 is maxed out running the MW now, a 2000w PSW might be too small.
If it is only a couple of lower watt items that actually need PSW, you can do the two inverter trick and save money. Get a small PSW inverter and a big MSW inverter. I did that set-up back when. Both inverters on the same battery bank.
I plugged the shore power cord into the small inverter so the smaller items could run on the receptacles as usual, and ran an extension cord from the big inverter around outside back to the galley area and back inside to plug the MW or toaster or kettle in.