Having heard good things, I've just tried putting an order in. When I get to the checkout page, it's telling me that "my guest paypal account has expired, and I must register for a full paypal account before continuing".
Now a) to my knowledge I've never had a paypal account, guest or otherwise.
b) I'll be buggered if I'm signing up for one. I have a deeprooted suspicion of anything ebay/paypal related, and I like to keep things simple, so pay by credit/debit card.
c) It very definitely says on the NDT website that "I do not need a Paypal account"
So have I missed something or is paypal playing silly buggers (see point b)?
If not, I'll be going back to CRC...
They're obviously using paypal to process your credit card payment - you don't need a paypal account for this though you can use one if you do - it's just a simple way for them to get payments through their website.
It sounds like a problem at their end rather than yours though. Drop them an email and let them know.
A 10 second google revealed the answer below, so your email address has obviously been used at some point for Paypal. Just use a different email address.
"On the live site, there is usually a spending limit after which a user can be asked to create a PayPal account. For information on these limits, you will need to contact support:"