They are bringing out a lower power hybrid next year, source: http://lexusenthusiast.com/2012/06/19/second-lexus-gs-hybrid-to-use-v6-engine/
"GB: That suggests there will be another engine to come for the GS.
YK: Yes, we have a lower displacement hybrid. It will come to European markets in the second half of 2013."
Can't believe they haven't got a better 2.5L engine though, that thing has been around for ages and the emissions and MPG are very poor.
Totally agree with the IS350 and preferably with the AWD as an option as well, in fact the ES hybrid would be a great car over here. The cars they bring over (except the CT) seem to be the expensive one's - if you want to get market share then would think the lower priced ones would help.
Another example of this is with the RX, the previous gen had a much lower entry price and was hugely popular. When the cost premium is £10k you have to do a massive number of miles to recoup (or be a business user) Australia get a 270, even smaller than the 350 model. http://www.caradvice.com.au/179021/lexus-rx270-review/