Start at four stars.Plus one star, because it's FINALLY a 128GB SD card.  I have been longing for this for quite some time.Minus one star because its performance is spotty.  I've been using one in a Surface Pro for a couple months now, and while the write speeds will peak at a sustained 15MB/sec, it often slows to 1 or 2, even in the middle of a large file copy.  I assume that's due to typical flash memory erase cycles or something, but I can't imagine it would be at all reliable for recording video to in your phone.In the end, I like it well enough to get two, but it's really only good for mass storage with low bandwidth requirements.