I mentioned this in another thread briefly but thought it deserving of its own.

Since getting a GRD2 I've been processing the DNGs using Raw Therapee. It's a freeware raw developer that, crucially, can use custom ICC input profiles, such as the excellent ones provided by JFI. Sean has a thorough review of these on his site, definitely worth reading.

As to Raw Therapee: I really like the results it produces, particularly the noise, which is very fine-grained. Shooting at 800 ISO on the GRD2 is no problem for me.

The program also has some good controls for exposure, including a Curves editor, but unfortunately some are missing, such as Levels.

It does have few downsides. The Color Noise control seems to work based off the image as it appears after the Input colour profile is applied, thus it has no effect if you're using the JFI profiles. Another downside is organisational: it's just not a very efficient program in terms of workflow, as it takes a while to switch between images (at least on my old single-core AMD 2000+ processor). Finally, it doesn't show the raw thumbnails as they'd appear with the Input colour profile applied. For the GRD2 this means thumbnails in colour, though since the GRD2 writes a JPEG too, I generally just use those for browsing and selection, and RT for the actual editing.