cozumelian
Guest
Uff, I feel for you Foo, seasickness is not a pleasant experience! 
I've taken the ferry many times and for the vast majority I've had a fine flat ride. You only have problems when the wind gets up and/or it's choppy. It'll be calmer closer to Cozumel if the wind's from the east, but if if the wind's from the west the opposite can be true.
The catamaran ferries tend to be better than the single hull boats too. You can't really choose which type you take though since it is luck depending what they have available when you get there (unless you decide to wait an hour or two for the next departure), but they use the catamarans the majority of the time anyhow...
Like Foo says though, if you are prone to seasickness it's worth popping one of those little magic pills before boarding and avoiding a spoilt day..!

I've taken the ferry many times and for the vast majority I've had a fine flat ride. You only have problems when the wind gets up and/or it's choppy. It'll be calmer closer to Cozumel if the wind's from the east, but if if the wind's from the west the opposite can be true.
The catamaran ferries tend to be better than the single hull boats too. You can't really choose which type you take though since it is luck depending what they have available when you get there (unless you decide to wait an hour or two for the next departure), but they use the catamarans the majority of the time anyhow...
Like Foo says though, if you are prone to seasickness it's worth popping one of those little magic pills before boarding and avoiding a spoilt day..!