This is the package:
Ilox Doble Full VOZ y DATOS 50 (75 Mbps first year)
The speed caps are probably 75 down and 20 up. (not sure on the up they never specified that )
According to their site, the extra speed is available as a reward for setting up automatic credit card payment. So available to anyone.
http://www.ilox.mx/iloxhogar/index.php/paquetes
I expect things will be slower in the evenings once everyone is hooked up. For now it's very fast and stable, no dropped packets or difficulty loading any websites.
Hopefully they can keep it like that.