I'm single, in my mid 40's and paid off my house a few years ago. Have never doubted my decision for a single minute. It's very freeing to know that if the economy tanks again and I lose my job/portfolio value -- I will always have a cheap place to live. Note that I said "cheap", not free. People sometimes forget that your monthly payment doesn't go away completely since you still have to pay taxes and insurance (and HOA in my case).
The ONLY downside I've run into in paying off the mortgage (and this definitely falls into the category of "first world problems") -- Barclays apparently thinks less of me as a credit risk since I no longer show a monthly mortgage obligation on my credit report. I cannot get a second credit card from Barclays to save my life, despite a credit score of 785. I know that that the lack of mortgage is only part of their calculation but it's still irritating to be "punished" for substantially lowering my monthly payment obligation.