I recently replaced my upper control arms, they come complete with the ball joint. The Lexus price was an eye watering £1,100 for the pair! I decided again to go with Rockauto, I didn't choose their cheapest parts, but even the ones I decided on with shipping and prepaid VAT the total was £93 for the pair. The quality appears to be pretty good, a very nice alloy casting of the main wishbone. I found fitting them very easy, I think the LS400 may be slightly different, and as I only cover about 4k miles a year I'm happy with my choice. As a DIY job I reckon I can do each side in about 40mins, so even if I had to replace them again I'm still quids in! I see Rock have them for the 400 for the same price.