Others will prob comment on the technical side of what the DV is actually for, but mine is also a 2005 GTi. I had my DV changed in June to a Rev G. Im glad I did cause the stock Rev C was indeed split! Now, I had a lot of mods done around then, and at same time, so cant comment as to what benefit that change alone mite bring, but for the sake of £37, id do it out of precaution alone! Id even go as far as to suggest that if yr current DV is split, this mite actually be the most important mod out there, if one could call it a mod!?