No, but I'd like to. They're a bit pricey for my taste.
> Also, my UHS-I card just died after a week or two of flawless and fast
> operation:
>
>
http://www.amazon.co.uk/exec/obidos/ASIN/B007JTKLEK
>
> I've read about other such mishaps, and I'm wondering if this could be
> because the Beagleboard (and many SD card readers such as mine) aren't
> UHS host devices and so presumably don't drop the voltage from 3.3v to
> 1.8v as the UHS-I spec calls for?
In order to comply with the SD card spec, all UHS cards must support
3.3 V signaling and power. If you see page 13 of the simplified SD
card physical spec version 3.01 [1], you can read more about this.
[1]:
https://www.sdcard.org/downloads/pls/simplified_specs/
Running a UHS card at 3.3 V as an SDHC card should have no impact on
life of the card.
-Andrew