OP here. I went to a few car dealerships yesterday - Lexus, Audi, VW and Skoda. I realise that the Lexus brand's principal competitors are primarily Audi, BMW and Mercedes however said dealerships were convenient geographically.
I was pretty unimpressed by the cabin of the Audi - it seems to have lost the stark but high-quality utilitarianism which I used to love about the brand. The new Passat was very good inside and seems to have got a lot better from the version which I drive. Surprisingly the Octavia was also relatively good. The deliniation of the interiors of Audi, VW and Skoda seems quite blurry and hard to define.
So, what about the IS300h? It seemed to be higher quality than the A4. However, it felt quite dark and a little cramped. This may just be me being used to driving a bigger car. The boot also seemed quite small and interior rear legroom was not as good (obviously).
At the moment I'm on the fence between a new Passat (2l diesel, DSG) and an IS300h. Both are in the same ballpark cost-wise. The Passat is roomier, has adaptive cruise control and is probably more fuel efficient. The IS300h is higher-quality, is probably more fun to drive, although it's similar fuel consumption wise to the Passat but is also a hybrid. Head says Passat, heart says IS300h.
I've submitted an on-line request for a test drive of the Lexus. One question - is a Lexus dealer likely to be less helpful if he knows that I would be getting a company car? On the one hand it wouldn't be bought through the dealer, on the other hand it would be sensible for Lexus to incentivise its dealer network to promote non-dealer Lexus sales.