||08-24-13 12:00 AM
My main criteria is having a model that allows the elbow pads to be slammed down on the regular bars, with no space in between. Many clip-on aero bars put the extension bars or other spacers above the bars and then the elbow pads on top of that, which I find is too high if I also put the regular drop bars at my preferred height.
My current favorites are the 3T models. You buy the clamps and armrests as one unit (alu' or carbon), and then the extensions separately (with a choice of 3 shapes and two materials). The extensions project straight out of the front of the regular bars, so there is no excess material protruding below or above the bars (keeping them as light as possible), which is not the case on many other models. Also, the pads are slammed down onto the regular bars, but can also be flipped up if you want access to the tops of the drop bars for climbing. The flip-up feature is not spring loaded as on some other bars (which can be annoying), but is fully manual, you just shift them up or down and then they stay there (the resistance is controlled by adjusting the balance between the tension on the two mounting bolts). I love this system and have two sets that move around between my bikes.