I have a 06 IS220d (Belgium) and it has now almost 195000 km ( 121167 miles) problem free...
I also bought the MINI VCI FOR TOYOTA & Software TIS Techstream (software + cable)...
As for the DPF I found several options in the software. A forced regeneration of any kind cannot not be started (forced) if the dpf is less than 40% full.
As I do drive the car euuhh fast(ish) everytime I check the dpf it's always near empty...
You have to use 'low ash' oil (I use Mobil 1 ESP Formula 5w30).... Although I must say that without the DPF the car should be more responsive.. Everything is possible but I wounder if the car will pass the emissions test here in Belgium...
I already have a custom made stainless steel cat back system in, and from what I saw even the cats can be removed because the last sensor is before the cats, so I will probably have those removed too.....