Hi jonfish,
This video is quite funny but it should also give you a sense of how difficult it may be to take the mattress up your stairs. It’s would probably be fine for most people (especially if they were in good shape) and would be easy for two.
There are good quality and value mattresses in every budget range and I would be very careful about putting too much faith in reviews when they are written by most consumers who don’t know how to tell the quality of a mattress. You can read more of my thoughts about reviews in post #4 here.
The first thing I would do is read post #1 here and the information it links to which will guide you towards finding the most suitable mattress with the best possible quality and value in your budget range. I think this post is essential reading for anyone who is buying a new mattress. It will also help confirm the quality and value of the Ultimate Dreams you are looking at. A mattress is only as good as the materials in it and there are better and worse quality materials in every budget range. The Ultimate Dreams mattress you are looking at has the quality of materials for example that is usually found in major brand mattresses or at mainstream outlets that sell for significantly higher prices (perhaps twice as much or more).
Hope this helps
Phoenix