Thank you MWM

A couple of followup questions

Do you have an idea of which lift and slide company makes the narrowest frames? Preferably one that makes matching windows as well

Do you think the lift and slide design has a particular advantage (vs traditional roller) in a marine environment?

The high end traditional roller companies offer all aluminum and stainless steel products. I'm still a leary because our current sliding glass doors (albeit standard models made with metals that rust) have fare poorly. Especially rollers, tracks, and locking mechanisms

European companies tend to make the better L&S's with narrower profiles personally from what I have seen. I would need to do some research as to which ones in particular have narrow stiles as I do mainly commercial for the last 15 years or so. L&S will be a better sealing unit in a marine environment (and just in general) due to the fact that the door drops down tighter to the sill. You just need to make sure that the guts are all stainless 316. Typically many companies all will offer a marine upgrade to this material, with the better companies using this almost as a standard (part of the higher cost).

Makes sense that L&S doors seal better

What are your thoughts about having the rollers at the top as in L&S vs at the bottom as in traditional slider? Intuition would say up high is better but wonder if it actually makes a difference in terms of longevity in a salt air environment

A heavy door like this will definitely need to have roller at the bottom. Some will have top rollers and some will just have guides. If you purchase a quality product with marine grade 316 stainless you should be good.

Marvin Signature Modern Multi-Slide Doors have 3" stiles. I don't know whether that's thin or not, but it's narrower than the Marvin Signature Ultimate Lift and Slide Doors which have 4" (or 6") stiles.

-- amateur

Thank you