Hi Qew,
Plus hello folks!
I've used an iFp895, which has identical parts and operation to the 799 as far as I can tell.
The preamp is acceptable for recording loud stuff, but a bit noisy for acoustic or dynamic stuff
The setup for levels is relatively easy, you can use headphones to monitor. I don't think IIRC that you can set levels on the fly while recording. The level is set on a 0-65 scale.
The onboard mic is poor and the options for int mic recording are limited. I always got artefacts with int. mic.
Ext mic options are good, and then you can record stereo mp3 at 320kbps.
Get a good mic to go with it, and it should be equal to most MDs.
Perfect for rehearsals, I use my 895 for my singing lessons.
However, this is not the same as being able to set and monitor levels as you can with ROCKbox firmware on the iriver H120 or H140. Quality of my singing lesson recording goes up several notches when I use the H120.