I'm on my third of these now, and I'll be buying more. Why keep buying them if they fail? Well, I've tried most of the other similar products that are around the same price or cheaper and this is much better - while it works. On average, the ones I've had have lasted about 6 months of use almost every day before failing where the cable joins the jack plug. I'm trying an experiment with my current one of wrapping this clearly sensitive area with duct tape while it's new to see if that extends the life any.
When they've failed, I've looked to see about repairing them myself, but the wires used is so fine that it's proved impractical and is also no surprise why it fails so easily. This skimping in this one aspect is a pity as otherwise, it's a great product - if only it took a bit more wear...but I'd still recommend it as the best choice, just budget to replace it fairly regularly
UPDATE: I have now ordered my 5th an 6th of these in anticipation of the 2 I have now failing so as not to be without one when they do. To clarify, I have tried 6 or 7 different makes of similar devices and won't be ordering any of the others again, even ones which still "work"