Calling All Trials Riders

Hi there trials people! Got a few questions for you.

I've been wanting to take up trials riding for many years - before mtb actually and am wondering how much difference a dedicated trials bike actually makes? Like does it really make track standing pivoting that much easier. Where does a trials bike really come into its own over a mtb. its probably quite a stupid question becasue of sheer size, weight and geometry but i'm tossing up weather i need to get one to sort of start jumping around and what not...

Also i no nothing about trials bikes so whats brands are good? models? How does sizing work? what should i be looking out for etc etc.. Are there any shops on the north shore that sell trials bikes?

Cheers,

Jono.