One other thing... comments in the Sony M10 thread on this board suggest that the R-09HR leaves small gaps in recordings when the recording levels are adjusted. If this is true, it's a complete deal-breaker for me. YMMV.
It's amusing that people are suddenly making this out to be a big deal, given that it has hardly ever been mentioned before.. With some practice, you can probably avoid changing levels during the active parts of the performance. Much like not needing to check levels.
Adjusting gain by definition impacts the source. Some gear does it better than others. The pots on many (most?) preamps will introduce noise when the gain is adjusted, especially as they age.
I've found the 7xx recorders also introduce artifacts when adjusting gain. The v3 is very good about it. The aerco is terrible about gain changes, yet in high demand.
Ideally gain changes will be "silent", but in practice it doesn't seem to be a big issue very often.