ben - If you are concerned, send it in to Barryvox and have them check it out. It's a computer - they can test it. Obviously, this is something better done in the off season... Have you contacted Barryvox? What's the warranty period?
An 8 year old digital beacon is probably less likey to have the same sorts of problems an 8 year old analog would (decrease in signal strength, frequency drift, etc.), but it's certainly worth checking out. I'd probably still have a high amount of trust in it.
There are few things you can do w/o sending it in: Some of your partners' newfangled digital beacons (DSP or S1? I forget which one) can check frequency drift of other digital beacons. Not sure how reliable that is, but probably reasonably so. You can measure your recieving distance yourself. Try it with a few types of beacons and see if it's different. Find a couple that have very similar recieving ranges and see how well they recieve you. I know you practice, so doing these sorts of things are just another way for you to check it yourself.
I didn't believe in reincarnation when I was your age either.
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