Hi. I've used them in the past and have been happy with them.
For me, their main advantage was fatigue reduction, as I couldn't reasonably stay in the simulated aero position (back low, elbows in, hands near stem) for the whole trial. Also, since these are shorty clip-ons, rhythm and stability were not greatly disturbed when shifting gears at speed, since this required only a quick lateral movement of the hands to the brifters.
Finally, since you're on road bike geometry, it may be worthwhile to get a fit assessment of your trial position with the shorties--I found the most success when altering the cockpit towards a slam position (not too hard with a Fizik Arione).
-good luck and have fun