Hi Andy,
Yes I think you got a good deal, you got an ARTR B4 for £92, you would be paying £80 for a madrat/Xpro new, but you would still have to buy all the radio gear ESC etc.
You were bound to pay more for the newer B4.1, but it came with the battery, better brushless motor and extra wheels/tyres, still a great deal.
Try and follow the setup info in this thread
HERE, when you get the cars. Don't worry if you don't have the bits or aren't sure to what the setups are referring we will help you when you come down.
The B4 is a great car especially for beginners and still wins titles.
Unfortunately we are not running this weekend (centre closed due to boiler failure) or next, but come down on the 12th if you can.
Look forward to seeing you then.