The Lexus extended warranty is very comprehensive.
I took it out on my two previous ISs and the claims just about exceeded the premium. In both cases I sold the vehicles with about 8 months of warranty remaining, I'm convinced it helped me get a good price with only a £25 transfer fee. I've never used the AA roadside assistance, but it is reassuring to have, especially when my wife travels 150 miles to see our daughter and granddaughter.
I took the extended warranty on my current RX and I've not made a claim in fourteen months of ownership. I'm very happy not to make a claim, just to enjoy the peace of mind. £1,000 doesn't buy you much at a Lexus dealership !!!!!