I looked at various options but went with genuine LR ones in the end. They seemed to be the only ones that fitted properly and looked reasonable. Expensive though!
I bought britpart ones as they were on offer for £15/£20. For once britpart have made a good product . I run the 90 with no roof all summer and regularly return to find puddles on the covers but dry seats underneath. They are always fitted, seem breathable in hot weather and the seats don't get mildew or start to smell either. Stick them in the machine when covered in oil and they come up good as new. seem to fit suprisingly well too.
I have had a set of Town and Country seat covers in my van ( a transit connect) for three years, they are really well made and fit nicely, cant comment specifically on their Landrover ones, but thought it might be worth letting you know how pleased I have been with the covers I got from them. Vehicle seat covers, car seat covers, seat covers, seatcovers, van, 4x4, agricultural, tractor