Just caught up with this thread tonight.
To respond to a few things mentioned...
Is the driver ok?
We had problems with the driver initially, and also I had buffering problems in my application (as did others). I have, however, managed to have it recording bit accurate for about two years now or thereabouts. The pocket pc driver is from pocket pc 2002, but it works because the cpu's in these systems are the same architecture as the 206mHz iPAQ's.
RE: flac
I recommend it only for 16-bit recording right now. It's flac level '0' because anything higher brings the cpu to it's knees. So, even if you record to flac and save, say 40% space, you might want to re-encode to a higher level later.
The 24-bit encoding isn't what it should be yet. Josh Coalson mentioned that it was an issue with the design and something about the rice coder. Anyway he has the code written to fix it, but he won't publish it until some hardware manufacturers make appropriate changes. He doesn't want to break anything, so that's good. However, meanwhile we wait.
formatting:
I recommend formatting right on the pda. I use a program called Storage Tools for that and it just takes a few seconds to format a 4gb drive on the pocket pc. The largest cluster sizes (64kb) are recommended for pocket pc recording. But step down to 32kb if you need to for your card reader (or maybe get a new reader).
reliability:
It works. Start, stop all you want to. It's robust software. And it stops on frame boundaries, does seamless splits on frame boundaries and so forth. One customer records the Dallas Symphony. He runs a Tascam DV-RA1000 and uses the pda as a backup at 88.2kHz. (They downsample for CD's). He told me that on one occasion when he had a glitch due to a bad DVD media that he used the pda's file to fixup the recording. Needless to say that made my day... He runs an X51v and 4gb Transcend 150x media.
Now you can turn the screen off while recording and split to a new file at whatever pre-specified interval you wish. Anywhere from 10mb to 4000mb. Or, you can press the button on the front to split. It has a file fixup feature which fixes wav header information of any files on the current path.
The pocket pc may not be for everyone. But many of those that have them seem to like them.
What's my favorite pocket pc? Well, I have tested a few of them. The X51v, the hp hx2795, and the H2210 in that order. The X51v has the nicest display of all and 2200mAh battery option.