I was originally on a Tellabs 611 when I ordered FiOS back in 2007, then when I moved apartments to a bigger unit I upgraded to a 612. Luckily I never had that crappy unit. Both of those units had no issue going over 35Mbps from what I understand, but I only had 25/25 (originally) which became 35/35. Looking at the FAQ it looks like that crappy ONT I'm thinking of was the Tellabs 610, the upload was limited to 29Mbps. Unfortunately I can't find a good pic of one.
I'm on a Motorola 1000GT4 now.