Recently got the Akrapovic DPs for the N54 from Harold at HPA. Had a great buying experience & he was really understanding. Sent me the invoice via PayPal & of course my account was a mess since it hadn't been verified. He gave me a couple of days to sort it out w/ PayPal before he was going to have to put them back up FS. Luckily I got everything sorted out & the Akra's are now on my car
Would def consider buying more from HPA, especially since they're known for retrofitting OEM parts and currently are working on a reasonably priced brake upgrade!