Problems with Euro map upgrade for Nuvi 310

After almost a month of trying to seek support, I have discovered Garmin has (in my view) a misleading policy on European Map updates for Nuvi 310. I went though the process of paying for an downloading a European map upgrade for a trip at a cost of £50 to save me hiring in Germany. It would not load to my Nuvi 310 and gave no error messages. I immediately contacted Garmin support by email and called the helpline, giving up after 20 minutes of hold music. FIFTEEN DAYS LATER ! they replied which began a series of email exchanges where they finally pointed out that my device was only designed for the UK map and does not have the capacity to take a European Map without upgrading the memory with an SD card. Despite many polite attempts, Garmin refuse to acknowledge any poor service or lack of information on their side and REFUSE to provide a refund.
I'm interested if others have had similar issues or advice on how to get a refund for a product I have never accessesed and now have no use for.

[Deleted by Amazon on 27 Dec 2011 16:34:22 GMT]

Yes Liam, I have a very similar problem with a Nuvi 255. This had the map for the whole of Europe, and I sorely regret paying about GBP100 for lifelong updates. The internal memory proved to be too small, so I had to get a 4GB micro SD card. Then I found I need MapInstall on my device which I can't download from the Garmin website. I had many other small issues which together caused me much loss of time, wasted effort, and growing annoyance. The feedback I get from Garmin is polite but factual without any evidence that they recognise my feeling of disappointment and frustration. They are doing a good job of losing me as a customer. By the way, double-check whether your device accepts SD card or SDHC card, and if the card you got is compatible. If you have an SDHC card then that might be the problem. Please note that you must ensure that the German map loads up to the SD card; if you download it to the main device then it will wipe out the original UK map. Good luck!