To each his own; from my viewpoint (and I tell all my clients this) the ipad might impress as a replacement and alternative to a dedicated remote, but in fact it's best used as an accessory or secondary controller. I believe that if you are using a quality controller in a well thought and put together system it will hands down be a better fit than an ipad.

That being said, it depends on how many people are using the system, how often the system is being utilized, what other remotes are involved, etc. I would get a dedicated remote and then look for an ipad solution as a backup.