Incidentally......
I used to be a very "active" sleeper.... Talking, shouting, walking were a common occurrence (OK being really honest I even woke up "private timing" an ex..... honest your honour 
) but it literally stopped when I got a memory foam mattress.
Just for the record, I promise I dont sell these things or anything, I know they seem a little pricey but I paid over £200 for an orthopedic mattress which I had to replace after less than 3 years because it'd worn so badly you could clearly see indents where we slept and that was even with it being turned/flipped every couple of weeks.
I've owned the memory foam mattress for about 6 years now and that cost around £350 (king size) and it's as comfortable as it was the first time I used it