I've had mine since mid march and haven't had problems. The unit has mostly been in a cover for that time so there hasn't been a good likely hood of a fall damaging it or anything. The lettering still seems to be staying on very well. I had thought it was getting a bit worn in some spots (letters) but under a bright light it shows that they aren't. Of course my vision isn't perfect so that was probably it.
All in all I have no complaints.