No, Onyx is just plain slow. PosterShop 6.5 was slow, Production House 6.5 was about the same and Production House 7.0 is even slower. However, that's an observational statement and nothing which I have tested. I've only ever bothered to run one of our plotters from the Onyx package and I only did this because at the time it was the only real option for the printer.
Don't get my wrong, PH7.0 is a much improved product. I just am a bit stunned about the claims of 30% faster processing times.
In general, even though it looks ugly, I still find I can get things done faster with Wasatch SoftRIP. My Onyx is on a dual processor machine with lots of bells and such and it's still slower than the single processor machine running Wasatch (and driving a number of indoor plotters)
As for where I am, I'm in Amherst, NS.
Have fun with your upgrade. Make sure that the version on your disks is the same as the one which can be downloaded from Onyx because this product is just out of Beta.
Rob