Is this a record? I have just replaced the DMS RedFlash 750 in my 2005 4/4. I believe it to be the original battery (I acquired the car with v low miles in 2007), so it's lasted 8 years. It hadn't completely died - I use a CTEK charger/conditioner - but wouldn't keep a charge for more than a couple of days without the CTEK being connected, whereas it used to go for weeks - immobiliser is the only drain.
As I'm off to the Isle of Man in a few weeks and had visions of not being able to get off the ferry, a change was due. The Odyssey PC925 is not identical but only a few mm bigger in each dimension, and has the same recessed terminals that take brass terminals fitted with an M6 bolt. My battery is under the bonnet, so stays nice and clean.
Google gives prices up to £165 with the best being Battery Megastore at £135. However I discovered the same supplier also sells via Amazon UK at just £123 with free delivery, so "click" and it arrived next day in the morning! Fitted easily and started strongly first turn of the key so I'm happy and perhaps the Amazon price info will be helpful to someone else.
http://www.amazon.co.uk/PC925-Odyssey-Dry-Cell-Battery/dp/B007NZ8RKK/ref=pd_cp_ce_0Nigel
