Since you are getting Shaker doors, it sounds like some of the cabinet companies are quoting thermofoil doors, which I would not want. Sounds like they will build the boxes & outsource the doors.

https://www.thespruce.com/thermofoil-kitchen-cabinets-3972521

Pros & Cons. Your call.

A shame that RTF got a bad name. Like Corian in a way. I have an "ancient" bath vanity. Not a single mark or chip on it. Bright white, wiped down every week for two decades.......not a single scratch.

Widh I could say that about some of the high end conversion varnish and even factory finished painted finishes I have done for clients

I am truly not sure what the finish is on my Ikea cabinets both my old ones in red high gloss and the ones I have now that are 12 yrs old and white high gloss and still look like new and I run a catering biz from my home. Wipe down quickly not one dent or mark on them.Plywood boxes are not better than particle board and are very stable as for white shaker doors IMO MDF doors painted with conversion varnish stand up very well and do not expand and contract like wood .

There are some high end veneers - I chose that for my bathroom because I couldn’t find a stain I liked. They hold up so well! I liked them so much I chose veneer for my kids’ vanities as well. My advice would be to see it and feel it.

Veneer isn’t chosen for an opaque finish. It’s for a stained finish. But since they are selling you hard with the useless “upgrade” to “solid wood” there no real telling about what they are trying to sell you on here. MDF is the preferred choice for paint anyway.