I'm still using my X5L every day! Couldn't find a good enough reason to replace it. SQ is pretty damn good in my opinion. The battery died, the headphone jack turned mono and the thumbstick wouldn't register "down" but I replaced all of them and it's working like new again. Getting 26 hours of batterytime on a
cheap Chinese ebay-battery!

I'm thinking about giving it a new HD since it's so easy to mod. 80gb sounds tempting but I thought I read something about incompatibility with every HD above 40gb? Let me know!
(the ebay-seller for the battery is called Megacapacity, there are several versions around $15)