there are still a few people working with udk.mainly 1 man teams on personal projects.there are 2 in the UDK projects so far(mine included)and I expect to see a few more move across to these forums very soon.
as you say,UDK is still a viable option for indie projects,and although you do need a beefy pc to run my game,its still a lot less than you would need for the equivalent ue4 project.
so hats off to you and hope to see you around this section often,i could do with some help in promoting my game.its an area I tend to lack in.