I am assuming that you are using the stock resonator. Do you have any drone or interior vibration under partial throttle in the 1500-2000 rpm range? Full throttle sounds good.
it does have some, but nothing i cant live with. There really isnt any at 1500-2000, but i do notice some at like 23-2500 at about 80 mph or so. at 60 there is none.
Its that loud with JUST a muffler? Now I know what my dads LX470 will sound like, except maybe a little quieter since Lexus probably put more resonators on their luxury vehicles. Nontheless, your 4R sounds great, very muscular V8 sound.
Here's some sound clips of my 2000 4Runner. I'm still working on getting a good quality video. The sound quality is really poor so to be totally honest, it sounds better in real life. Again, i'm still working on getting a better clips.