MK5 PD105 won't have it but I've seen them on PD105 Audi A3 (2008) that I've tuned.
DPF's are a bad idea in their design as the basic principle of the design relies on an assumption that the car will be driven long enough to allow regen in the background. However many people do short start/stop type journeys meaning the DPF never has long enough to regen and the lifespan of the DPF becomes drastically reduced..
We've been DPF Deleting for a long time now, in fact it's fair to say it's a big part of our business now as people are buying 3- 4 year old used cars that are 80k miles and above and quickly realising what a problem DPF's can be.
We do offer DPF safe tuning, so we ensure that set thresholds in the ECU are not breached, but sooner or later your DPF will need removing or replacing. When they start to block up, they push all the ash content back up the system and clog up inlet manifolds, EGR valves, vaccum pipes, sensors etc.
Have a look at our Facebook page in my signature below if you want to see some examples of what DPF Deleting involves and what the insides of a DPF actually look like once removed... you'll soon see why they're a bad idea.
