I know something about replacement windows, having replaced 29 double-hung and 3 casement windows about 4 years ago. My old windows were cheap builder's grade (wood-frame, double-glazed, poorly installed) and were 21 years old at the time. I originally planned on wooden frame windows made by Anderson or Pella, but the local dealer quickly talked me out of those, even though he sold them. Wood frames are expensive, swell & shrink with the seasons, and require painting & repainting. Anderson does make fiberglass frame windows that don't swell & shrink, but they are still expensive. I was less familiar with Marvin, but they also seemed to be good, if less advertised in this area.
I eventually went with insulated vinyl,
Ideal Ultratite. They come in factory-finish colors (never need paint!),and cost about half of what wood frame windows cost. I got double-glazed with an infrared reflecting layer called LowE glass that added about 10% to the cost. Four years later, I'm still happy with them.
It sounds like you're decided on Marvin windows. They're locally made, and they are probably supported by local builders and installers.
I would guess LowE glass might be standard. If not, I do recommend getting that. I find it makes a noticeable difference in both winter and summer.
In Minnesota, does triple-glazed glass make sense? In Maryland, it wasn't worth the extra cost.