Don't get me wrong, Mortal Kombat 3 is one of my all time favorite games but I had an MK3 as my only arcade machine for more than 10 years, so at this point it's pretty stale and I rarely play it.
I've already agreed to sell it to a friend who lives locally so it wont be going far
Double Dragon just isn't my cup of tea, however if I ever clear up some room I plan to fill the beat-em-up niche with a TMNT 4-player cab