"And if you're thinking about doing this on a 2nd gen, read this"
I have done it with a DL650 (K7), no problems so far. I have no sheets with the original ignition timing, but I bet it's same as for SV650 2. Gen.
Performance has increased, but this isn't the only mod so I don't know how much the +4° key is worth in "stand alone".
Edit: argh, forgot to mention that the lowest fuel grade in europe is 95 octane, so maybe it will not work well with the low grades that are used in US (87 octane?)?