Quote(an r4 needs...) to be modded under any circumstances if you are considering running mic>deck.
I totally disagree, there's plenty of decent stock R4 sources out there. As mentioned previously, a huge factor for sound quality on a stock R4 is about using as little pre as possible (which isn't a bad idea for anyone with any gear). This is accomplished through picking a good combination of mic-in/line-in and pad/sensitivity on your mics. With experience, I rarely ever need to put the gain past 12 'o clock (or even 11 for that matter). The R4 pro makes this even easier b/c it has seperate gain/trim knobs -- which is very nice. Anyway, just decided this thread needed a different perspective on that front.
YMMV of course, and tapermark's experience is a good example of that, cause that obviously sucked...