I booked into a testing station yesterday and once i arrived they told me that they couldn't test it because the car was over 3000kg and therefore falls into class 7.

Last years MOT states class 4.

I took it to another tester today who said it was class 4 and it sailed through.

Anyone else come across this?

An FFRR unless fully laden doesn't weigh over 3000kg, IIRC they are 2700kg or there abouts and less than an RRS/D3/4 as they are a monocoque shell and the others are shell and chassis  FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Sounds like they were talking crap, the weight as KP says is around 2700kg

Sounds like a lucky escape then. If the muppet can't tell what class a vehicle is in the you probably don't want his "expert opinion" while testing your car.

I'd also make representation to VOSA about the garage as well. Ejits who don't know the rules should not be allowed to continue enforcing them.