Heck Skalinder got his HDP2 and R4 from Oade. I believe both had problems if I remeber correctly.
My ACM HD-P2 has a known slow firewire connectivity / transfer issue,
as noted here. This is a Tascam issue, not an Oade issue, though obviously due to the mod voiding the warranty Doug's going to resolve it for me. Additionally, I experienced odd symptoms with my ACM HD-P2 I've since been unable to duplicate,
as noted here. IME, this is again a Tascam issue, not an Oade issue, but at this point I'm chalking these up to a fluke as I'm completely unable to replicate. Finally, I had problems recording with this unit -
noted here - that I believe are media-related. Suffice it to say my HD-P2 experiences have not been terribly positive so far, but based on the testing I've done, I'm confident my issues are Tascam / media related and have nothing to do with the Oade mods. Doug's customer service and willingness to work with me to address manufacturer's issues is one of the reasons I go with his mods.
My R4 had ch4 polarity inverted relative to ch1-3. This was a known Edirol issue. They fixed it by simply re-wiring the units affected, of which I got one. When Doug implemented his T-mods on ch3-4, he modded as though the R4 was stock, i.e. wired correctly in the first place, effectively un-doing the Edirol fix for the inverted ch4. AFAIK, my R4 has not had this problem resolved, but it's through no fault of Doug's - he offered to fix the unit immediately upon discovery of the issue, but I simply didn't have a convenient opportunity to do so before I sold it, and neither, it seems, has the new owner. As soon as the new owner sees fit to send it in, Doug will re-fix the Edirol fix.