Do you advise buying bus tickets ahead of time in Manzanillo area in very eary Dec.?

in manzanillo, no. but i also recommend it because often the POSTED schedule is very different than the actual schedule. last time i was there, i showed up for a 6am bus that was up on the board, but didn't actually exist. THEN the next bus which left a full 12 hours later, was cancelled...and the night went downhill from there. so yeah, go a day or so early and buy the ticket, just so you'll know exactly what time to show up. the station is not air conditioned and it has very little to eat...no hot food at all. you don't want to sit around there longer than you have too. ETN goes to manzanillo, but they have very little choices for leaving manzanillo...so, although they are the best, depending on where you are going, you may need to opt for another line. the next best would be the primera plus/flecha amarillo lines.

No ... not to get a seat. I you want the best choice of seats you may visit the bus station a day or two early. ETN is the only company that may have alternative ticket offices. Ask around when there.