If there is a choice of getting the 300 or 430/350, and money is not a concern, then its a no brainer.

 

^ All things being equal, I can now get a 08 GS460 for cheaper than I paid for a GS350 last yr. Human nature being what it is, the quest for more HP never ends - if I weren't locked into a 3 yr lease, I'd be seriously tempted . . .

 

the m3 rides better than the is-f, that's all i can say

 

I guess whether one thinks it's underpowered or not differs by person.. I have a 06 GS300 AWD.. i'm a VERY VERY easy driver who enjoys taking my time on the road, enjoying the quiet and comfy cabin listening to music off my ML system... to me, I have more than enough power to kindly overtake very slow vehicles or make safe lane changes (and that's all i really need)... If u ask me why not just drive an ES, i can tell u that I'm not a big fan of the ES, the ride is too cushy for me and the cabin is nowhere close to what I expect in a car (afterall, the GS is one grade up from the ES and one grade down from the flagship LS by Lexus's lineup)... My GS300 with 50less hp, i still drive on "normal mode" and rarely flips the switch to PWR mode.... :P snow mode best for snowy days in Toronto.... when i test drove the GS350 and the hybrid, i pushed them hard, they are much faster and stronger i agree, but i just dont drive like that =D... im happy with my GS300 AWD getting 7.7L/100km, enough power and great fuel economy for me... if anyone trusts consumer reports, the 2006 GS300 was the only vehicle of the 3GS to have above avg used-car verdicts coz of least avg number of issues reported... to me, thats quite important coz i drive the car till it dies...

 

The 2006 GS300 is a very good car.
It has reasonable power for 0-100 in 7.3 seconds.
The 3.0 is Lexus and Toyota's sweetest engine; the 3.5 is coarser at the top of the rev range.
It has reasonable turn-in, shortish suspension travel, reasonable damping, and fairly high levels of terminal grip on 17" rims.

The GS460 V8 on 18" rims is very different.
The V8 has more bottom end torque, however not much extra power overall.
On the downside, the V8 makes the GS too nose heavy, and if you're really into cars, you can feel the extra weight in the nose, and the reluctant and sluggish turn-in, with less terminal grip.
Worse, the 18" gives a constantly choppy ride.

The old ES350 is interesting.
The old ES had "longer" suspension travel than the old GS, thus the old ES rode better.
The old ES wheelbase was almost as long as the GS.
However, the ES is front drive and suffers from a heavy nose, that is reluctant to turn in; furthermore, that heavy nose has less front grip than the GS.
The torquey 3.5 cannot put power to the ES's front wheels properly, because the of weight transfer to the rear wheels.
Finally, the GS has aluminium bonnet, and aluminium suspension components, such that the GS300 is actually lighter than the ES350.
The multi-link suspension in the GS also keeps the wheels more perpendicular to the road, than the ES's simple MacPherson strut and semi-trailing arm rear suspension.
Thus, the front drive ES is the most compromised and budget car of the three...