There are different versions of the Modtray boot. Some have a zipper and some do not.
I owned the non zip Chelsea boot several years ago. They were my daily walking boot for my suburban-ex-urban neighbourhood where I hike up hills, on sidewalks, streets, and some chip trails.
I found them comfortable for the most part. I had to add an extra insole / plantar fasciitis lift. The one drawback for me is that the toe was almond shape and over time I could begin to feel cramped in that area if my feet swelled. But overall I would call them roomy and even wide and keep in mind that I walk on very steep hills and I have a narrow heel, so my feet can slip forward in most boots (which is what eventually caused some slight discomfort at times for me).
I wore them out in a year of very hard wear. I am super hard on the footwear I wear for these jaunts. So heels wear down, insides wear out, shape goes.
They were totally waterproof for me and I walk in serious rain and even through puddles. I can't remember ever dealing with a leak.
I didn't make a direct replacement because I wanted to try Blundstones again for ths purpose. The Blundstones are wider in the toe box which is good, but also wider overall, which for me is bad.