On my MTB I used to get a LOT of male area numbness and sharp pains with the stock seat. So I bought a Serfas RX Gel. It was a lot more comfortable and no more numbness pain, or at least very very little. But now my main issue is that after riding for just 2 or 3 miles, I'm still not tired or anything, but I get a very intense dull pain in the back upper part of my left leg. Its always on the left side, its like at the top of the hamstring. Its a very dull pain over an area of about a 4 inch circle. I don't remember this happening with my stock seat. Is it something with the new seat or am I doing something wrong?

The harder they are, the more comfortable they are in the long haul. I'd get a wtb speed V or Rocket V Stealth they are hard enough to be comfortable in the long run and has a v channel to take away that male area numbess and pains.

Sound's like the dude's ass is having a stroke. Saddles are very user specific so what works for me may not for you

If you're not using them already, try a pair or padded bike shorts or padded liner shorts that go under your regular shorts. They make a big difference in seat comfort.