Rope releases are just a 2 foot section of rope wrapped around the pylon that the operator lets go of to release the rope. Its pretty idiot proof, but I don't think a great idea for tournaments. In this past weekend's regionals, I saw at least two trickers lose a pass because the operator accidentally let the rope go or it got pulled out of their hand. The rope releases only made up about 25% of the skiers this year, mostly in the collegiate contingent.
A lot will depend on how you intend to use it. If in a tournament, the method of attachment makes a big difference as to how hard it it to attach and remove. Many times you don't have much time, (couple of minutes at best) to do that so ease of attachment can be important.
We have always used A.R.E. and KW with good luck. If permanently attached, the A.R.E. is good as it is fairly small and stays out of the way below the slalom attachment. I know the masterline works well but can be confusing on attaching the rope correctly. The robbins is similar to a rope release in that the operator has to hold the rope to keep the line attached. I am not familiar with a Trick Systems or Vortex release.
Hope this helps.