I have been shooting this SBR MPX for about 7 months now in USPSA and Steel Challenge with an 8" barrel. I have tried several different configurations. This setup with a 4" barrel is the latest mod:
Shot it at a steel match this week for the first time with the 4" barrel and I like it much better than the 8" setup. Placed 3rd, with 1st and 2nd going to PCC shooters as well. Local paper match next week to try out the new CT laser. Will be handy for a few situations..