I had my iRiver H340 for less than 30 minutes before it ran rockbox. At the time of purchase it was, to my knowledge, the only way to get gapless playback and high capacity (40GB isn't enough now but it was the best you could get back in the day). I've tried it with a replacement SSD but while it works it is quite flaky and needs regular resets.
It's a shame there are very few high capacity players on the market now, I would love to get a new device which supports:
Lots of storage. Enough to encode all my CDs and a few 'try-before-you-buy' albums. Ahem.
Bookmarking capabilities that work with all files (apparently ipods require you to define things as an audiobook before they support bookmarking)
ogg support so I don't have to re-rip my CDs (I'd compromise on this if everything else was offered - it's only a few weeks of feeding CDs to the PC)
No need to 'make my own playlists' or any other such carp unless I want to. Music already comes with pre-defined playlists: also known as albums.
If this ever happens it will most likely run rockbox - I doubt the hardware manufacturers would do as good a job.
To Linus and the rest of the rockbox devs. Seriously. Thank-you.