The Protx integration was initially created for my 3.3.1 installation (a paid for modification) at
www.martial-art-shop.com.
It was ordered and paid for in January but it has only just been completed as a fully working add on as there were many errors with it to begin with, it does however now work fully, passing all the relavent information accross with it ie. customers address, email, postcode and cart contents, it also passes back the transaction details to be stored with the order and because the email and postcode are present it generates an email to the shop owner and customer with the transaction details and the CV2 information can be checked (better security)
For those of you that don't know the Protx system, it is better than most "Form" payment methods as it encrypts the information before it is sent, as weel as using SSL of course.
It is also a lot cheaper (you need your own merchant account) at 5 pence per transaction and no monthly charges, it's got to be the best out there