A sierra cosworth 4x4 running 330hp will be perfect for everyday use , thats what they were designed for!!

If you get a low mileage example then the head gasket should be fine , when it goes fix it but not before, also when you have a low mile example other mechanical parts should be in good working order.

I would really spend the extra cash and go for a T34 with a .48 exhaust housing as well to get a genuine 330hp, this will bump the price of the conversion up but well worth it imo