What's the best bus company in Mexico to travel from Morelia, MX to Puerto Vallarta, MX?

I'd like to have answers from people who've taken this route and if you can link me to websites, that would be great. Thanks

A very comfortable bus line that works in that area is ETN (Enlaces Terrestes Nacionales). There is no direct bus in this company between Morelia and Puerto Vallarta, but you can take Morelia - Guadalajara (3:30 hrs - 290 MXP) and Guadalajara - Puerto Vallarta (5:00 hrs - 405MXP).
(The webpage is in the sources section)

Primera Plus is other option, they have a direct bus between Morelia and Puerto Vallarta, the buses are comfortable (not as the ETN ones) and it is cheaper (590 MXP)
(The webpage is in the sources section)

Other bus company called Autobuses de Occidente is almost certain to have a direct bus between those locations, unfortunately Autobuses de Occidente (not ADO, which is widely known, ADO is Autobuses de Oriente) has no webpage i know of. Autobuses de Occidente has some buses that are also comfortable (those are known as Via or Via Plus, being the later the more comfortable, as the Primera Plus ones) although not as comfortabale as the ETN ones, but they are cheaper, have more departures and more destinations.

Look nowhere else... ETN (Enlaces Terrestres Nacionales) is the way to go... best and most comfortable buses in all of Mexico; better than Elite, Turistar Ejecutivo, Futura and Estrella de Oro...

ETN rocks!!! you won't regret it...especially on the tedious trip to vallarta. it looks so close but it's not! ETN will make your trip much more enjoyable.

all three above are right it is ETN