It's a personal preference. Low profile is 5" and regular profile is 9". The issue is that most of today's mattresses are so thick that the overall bed height can be too high for some to comfortably get on/off the bed. Furthermore, if it's too high it can become an issue with some types of bedding where it does not come down far enough on the sides to reach the slats. What you need to do is figure out the total height of your bed after the mattress and boxspring is on. To do that, you need to add up the thickness of the mattress + boxpsring + height to bottom slats. I recently bought two mattresses and for both I opted for the low profile which puts the bed at a perfect height such as we had before with our older mattress and box spring.

I just spent hours and hours looking for a 9" drop bed skirt. It should not be this hard!!! I bought the low profile box springs, aka bunky boards (where did they ever come up with that name!) for 2 queen beds for a loft with a very low ceiling height. Thank you, thank you, thank you for all your posts. All my typical online shopping sites failed me, and I thought I checked Amazon, but perhaps not. Looks like the more expensive one there is the way to go. And according to reviews, I know I'll have to beware of color. Here is another alternative I almost went with as a last resort - a box spring "wrap". And as far as I could see, it's available in black, stone, white and ivory. Wasn't exactly what I wanted, but thought it would be better than the actual box spring I'd been looking at for over a year! The reviews seemed good. Just thought I'd throw it out there, but I'm gonna go with Amazon's 9" drop since I spent so much time looking for it!!! https://www.overstock.com/Bedding-Bath/Sleep-Plush-StyleWrap-Black-Fabric-Box-Spring-Cover/11552337/product.html

Are you sure this guy is not just an idiot and hit some blocking, duct or something. There is no way that the ceiling/floor is so shallow that it won't allow a junction box to be installed. It would not be able to support any weight at all. Are the structural members exposed (joists, beams etc) and he is drilling between them into the subfloor above? It doesn't add up.

I also found Halo RA4 shallow gimbals. http://www.cooperindustries.com/content/public/en/lighting/products/recessed_general_purpose_downlighting/selecctable/_977687.html They are only 3.3" deep and can mount in a ultra shallow 3.5" new construction box. But no ICAT box is rated for foam insulation and they don't have a very good beam/field angle