I have my Roadster 1.5 in for the annual service and there is a issue with the battery requiring a sheet to be replaced. The best explanation I was given is the sheet has some resistance and it will eventually go bad and other sheets will eventually go bad as well. I haven't had any loss in range/battery capacity yet. The question I am faced with is do I repair the battery & replace the sheet for $4,500 or do I keep driving it until the battery goes bad or range is too low for regular use and then upgrade to a 3.0 battery? My take is if I have a good chance of getting 3 yrs/20k miles out of this battery before falling below 50% I'll kick the can down the road and upgrade to 3.0 then. If there is a good chance this battery will die in the next year and the car is unusable I'd rather pay the $4,500 than upgrade now for $29,000. Does anyone here have experience in how long it takes for other sheets to go bad if the first bad sheet isn't replaced? How much time/mileage could I get out of this battery before it degrades to below 50% of its original range? If I do repair the sheet is it likely other sheets will go bad soon as well because of age mileage? My roadster currently has aprox 23,000 miles and is 8 years old. Appreciate your input so I can make the right decision.