That will be the N22B or i-DTEC engine, which comes with DPF. As with all DPF engines, the DPF is a "consumable" item, and costs over £1k from a dealer, although someone recently posted a link to somewhere that sells DPFs for i-DTEC for about £400. You can also have the "DPF delete" done instead, recent one here -->
http://typeaccord.co.uk/forum/topic/23644-premier-tuning-8th-gen-idtec-type-s-stage-2-remap/
Recently there was someone who had a fault with the ISV , see this thread -->
http://typeaccord.co.uk/forum/topic/23580-2011-accord-22-diesel-este-intake-shutter-valve/
Then there's the DMF which will also need very expensive replacement at some point in the car's life.
Other than those issues, by all accounts it's a very good car.