It's more mountain bike style than actual mountain bike. The front suspension looks extremely basic and the rear wheel has a freewheel which wouldn't cope with serious off road use. You can probably get a real mountain bike from about £250 with a freehub based drivetrain and entry level suntour forks if you shop around. Look for a 24 speed drivetrain and a suntour fork. Suntour XCT is their entry level XC fork (28mm stanchions) and ok for light use off road or lighter riders, Suntour XCM is their stronger 30mm stanchion model which is a pretty reasonable entry level fork, I think there is a XCM 32 which has stronger 32mm stanchions again so a bit more heavy duty and then Suntour XCR which I think is 32mm stanchions with an air fork option. I've seen XCM's on fairly low cost bikes. £200 is close to getting a real entry level mountain bike that it seems false economy not to spend an extra £50.
Cheap and cheerful. Hard to tell if it's a good price or just an over-inflated RRP, since it appears that literally no other retailers sell this bike.