I'm not a developer, and I'm a Linux newbie but so far my N800 experience has been positive. Maybe I'm just lucky, but mine has been 99% stable with the factory installed firmware (It randomly rebooted once when I left GAIM running one time) and haven't had any issues with the latest firmware so far. I agree that it isn't as polished as it could be, but web browsing is much better than any WinMo device I have used. I would try the latest firmware and see if that fixes your reliability problems. If you don't want to take the time to download a Linux live cd to install the firmware, then don't and use the Windows installer they just released (http://europe.nokia.com/A4305010). I don't know how well that installer works as I actually wanted to use the Linux flasher to learn how to use the terminal in Linux. Took about a minute to flash the device after downloading the latest firmware.

I have these apps installed on mine and most of them work fine:

Canola
Maemo Mapper
Kismet (a little buggy)
Aircrack-ng (a little buggy)
GPE Suite
Maemo Periodic
GAIM
FBReader
FM Radio
OMWeather
Load Applet
Xterm
Minimo (buggy)
Midnight Commander
MPlayer (a little buggy)
Maemo Stars
Maemo Recorder
MaemopadPlus

Prior to owning my N800 I had practically zero Linux experience as I have been mainly a Windows guy. I haven't had any major issues with installing/configuring things, then again I'm willing to put a little time into reading the instructions/ and or guidance of people on this forum. As a gadget lover myself I am amazed at the potential this device has. Name a WinMo device that can support 2 SDHC cards (albeit with a custom kernel right now), has the wireless sensitivity the N800 has, and the battery life. If they ever get USB OTG working I'll be in heaven as I can forget lugging my laptop around to backup pictures from DSLR's memory cards. With 32GB SDHC cards expected to arrive later this year I will have 64GBs of drive space in the palm of my hand and probably double that a year later.