They're more of a commercial tyre for pick-ups and LDVs IIRC. Designed for long life but not for grip in slippery off-road conditions.
Is £250 a good price? Well, how long is a piece of string
If it's for 2 tyres, then I hope you're getting vaseline included in the price. If it's for 5, then maybe ok. What is very good tread? 95%? 50%?
On the sound sof it £250 might be a fair price but not a bargain IMHO... but that's hugely subjective without any facts/details.