i have 2 halos both with V35
they are really good, speed ranges from 17-35 bps, mine is set around 27 (4 flashes) if you read the instructions its really easy to know how to use (or i can explain if wanted)
the only problem i have had with them is the fact with all halos, you need to disconnect batteries after use (after a tourny/training), otheriwse it drains them over time which is a bitch when you didnt know this a take them to a tourny and have the red flashing light during a game
the speed, is simply awesome