I do realize that the "by the book" way to do this is pay sales taxes to PA and do required paperwork in PA, since I will keep it there for at least a year. When I move it to MD, follow their requirements.
The other option was skirting the rules a bit.
I just need to confirm that if I can prove that I paid 6% to PA, MD will not come after me for even more sales/excise tax a year later. I do realize that I would still have to buy the MD recreational sticker.