Yes, take your point and I must admit after doing a bit more research and given the condition of the rest of the car I may as well get the pukka parts, unless something radical happens and I can't see that.
Mine has only done 62k miles but is fairly mint considering it's an '03 - it would be silly to spoil it.
I have used Lexus parts for belts, brakes, discs, radiator etc so why not the exhaust.
Thanks for all your inputs.