The new 257 is now available which is the replacement for the 153. I just came from the dealer and was playing around with it. It just got done with PDF. A lot of improvements are evident. Greasing is easier ( which is a good thing)., hyd coupler, three aux hydraulics. The interior is like the 200 series Taki machines.
If you have a 153, it makes going back to regular swing boom mini ex difficult. What these things can do is amazing. A buddy of mine who's company has three of them got his 257 a couple months ago. He says its better in every way. Faster hydraulics, more flow, more push power. Mine is the one I was playing with today. Cant wait to pick it up.