Twin scroll can be effective for quicker spool and better torque. The Subaru's have been using it for years on the JDM models. Mine was originally twinscroll, but this hampered it if you wanted a lot more power using stock housings, as this is ultimately the limiting factor. Move to a conventional garrett fitment and rotation, and the world is much more your oyster.

However, already achieving over 600ftlb of torque and 1bar at circa 2800rpm on a single scroll 3076, I doubt I need to worry too much about spool or throttle response to warrant even looking at twinscroll. The next build maybe a different story!