I have a 36" setup with the Shadow handle, and a 29" with the T-bar. Both are flexible enough in setup to work for a range of riding but my experience is that the Shadow handle seems better suited to road/distance use, and the T-bar to to XC/Muni.
I have never installed the rear T-bar on the Shadow handle, but instead cut the curved bar short and left the straight bar long. There are some pictures of my initial setup in this post.
Having never gotten into riding long distances on road with the 36", the short handle sees the most use though recently I have flipped it so the bend is down:
This setup preserves the plastic grab handle so it can be used in situations where a closer hand position is more effective (mounting, hopping, etc).
The KH T-bar on my 29" is setup for XC/Muni use in Turtle’s style. The plastic grab handle is replaced by gripping the tube of the T-bar. The bar ends are far enough away to provide support when cruising. Overall this is my favorite setup and works well for me on trails and on the road.
