Honestly, the TechT bolt isn't going to make that much of a difference in game. It does help with consistency, albeit only slightly, by reducing the velocity differential when firing at a high rate. But, you can also improve consistency by upgrading your inline reg or running a nice regulator on your tank. If I was going to drop any money into my Etha (I've been using it stock for almost a year now), I would pick up a smaller bored barrel back and a violent trigger. Maybe for ****s and giggles put in a Virtue or Ape board, but I love the simplicity of the Etha board and I really don't need all the bells and whistles that come with aftermarket boards. I've heard they've helped with efficiency, however.
I just put the Virtue OLED board in my Etha, and absolutely love it! It is a little speedy at 187.00 but when added to my EMC kit, it makes for one hell of a woodsball gun. I also put an Apex 2 barrel on it, which I prefer over stock. Having the OLED screen in the provided grip panel makes programming very fast and easy.