AE Rendering left me wondering...

Hi Guys,
I have been using AE CS4 to render some clips captured by Sony HDR XR100 which records in AVCHD format at 1080i.
I was just doing some test renders with an adjustement layer over a 1min clip. Only Effect I applied was Magic Bullet Looks. And it was taking 1hr 20mins to render. After reading on this forum, I converted the clip using Neoscene Demo version and it brought down the time to around 20mins!! Massive Improvement I must say.
However I'm wondering if it is still too much for a 1min clip with just Looks applied.
I run a AMD QUad COre with 4gigs RAM..Running Vista..
Is this the normal time taken to render out 1min clip or Am I using the render settings wrong? I used Video for Windows that gave me uncompressed AVI mammoth file.
can you tell me some more tips to use render settings effeciently please?
Is Magic Bullet really heavy on the system? Should I just stick to basic color correction?

I'm planning to shooting a feature soon and if this is how long it will take...I might have to reconsider my workflow and work in short sequences....dunoo

Thanks for taking your time out and reading