Hi,
I see you are in Brisbane.
Best bet is get yourself over to Premier Lighting and have a chat with Darren or David. If they arn't too busy he will happily pull out their various HMIs and fire them up for you to see for yourself the output and differences between PARs, Fresnels etc.
*disclaimer - I don't work for Premier but when I was just starting out they were extremely helpful and encouraging, and still are.
Cheers,
Mark