not too sure yet if I want 2 or 3 heads/QUOTE]
I assume 3 is better than 2 but why? Can you explain Garry?
Garry's setting up for Focus ATM and I don't believe he surfs the forums from his phone

so if you don't mind I'll have a go at answering....
3 gives you more options. 2 on the back, one on the front. 2 on the front, one on the back, 2 on the left one on the right etc.
USED CAREFULLY more lights can give a more 3 dimensional look to the subject. But there's plenty you can do with 2 lights. And loads you can do with 1. First picture here
http://www.frankdoorhof.com/site/?p=1286 for example is 1 light and I often use 1 light when on location.
If budget is tight then buy fewer lights and spend your money on decent quality and modifiers - you can always add later. If you want a one stop solution then the kit builder will save you some money.