As long as the launch controller is a heavy duty type (e.g. Gell-Cell and Heavy Relay), why not just use the igniters that come with the motors? As long as they work well with single motors and the controller provides enough juice for the entire set, won't they work just as well in a cluster?
One thing to keep in mind, though, is that the standard for reliable launches for clustered motors should be markedly higher than for single motor launches. I.e. a motor/igniter/setup combination that ignites 95% of the time is not too bad for single motors. One launch in 20, you'll have to push the button again, re-attach the clips, replace the igniter, etc. Livable.
That same rate (per motor) in a mere three-motor cluster results in about an 85.7% success rate, with the remaining percentage divided among single, double, and triple engine failures. Worse, the most common failures are the ones where some motors fire and some fail. This can be a bigger problem than the all-or-nothing results. The rocket may leave the launch rod unstable, or it may fail to achieve enough altitude to safely recover. At the least, it will waste some of your engines on an unsatisfactory result.
For that reason, the igniters, launch controller, wiring techniques, etc. must be of a higher standard if cluster launches are to be successful.
I guess dipped igniters are more reliable, especially for mid-power and above?