I wasn't all that happy with Lion, to the point that I rolled back to 10.6.8 Snow Leopard. Mountain Lion was useable.
I completely skipped over Lion, and only had Mountain Lion because it came on the new iMac I got via AppleCare when my old iMac died. I've since upgraded to Mavericks on both the iMac and my MacBook pro, and it's been pretty solid. In fact, my iMac now runs better since upgrading, which isn't what I was expecting. I bought an old MacBook for my mom which I will be loading with Snow Leopard, which should be good enough for her.