I'm with col on this one, i've got an 07 plate IS220d SE, and it's the bollocks, love it to bits. The seats are among the most comfortable i've ever sat in, to hell with the back ones as it's my car so i don't intend to have to endure a drive in the back, but i've managed to get some of my tall friends (up to 6" 5) in the back when neccesary so it's not too bad. I'm also 6" 2, and there's no problem with my height in the front whatsoever.
As for the boot space, i can fit a toolbox, first aid kit, 65 Watt Bass amplifier and a PA speaker in it, so it's pretty decent sized, but not the biggest out there.
Hope this helps.