Using the internal flash on the thin-client? It'd be worth keeping an eye on the performance of the internal storage in case that's worn (though I'd expect the OS to report something). You talk of turning it on/off - I'm expecting that is through a controlled shut-down and not just power switch?, might be worth googling if the version of CE (I think I saw a post that said you'd installed CE) you're running is compatible with the flash storage and is fully syncing device writes before shutdown.