OKAY what exactly is a gua gua is it simply a bus with a fancy name or is it a form ot tuk tuk ?
A Gua-Gua is like a Tap-Tap is like a Dolmusch is like a Tuk-Tuk.
Basically a minibus or small coach.
On the south coast you always get your own seat and they are half decent. You do not have to hang out the door driving down the highway like on the North coast.
There is little or no regulation for these vehicles and what regulation there is is not enforced. Occasionally they have big crashes. Last week one driver had a heart attack and drove into the sea killing a dozen passengers. Last year one crashed on your very route and killed a whole bunch of Italian tourists, although this could have been a privately owned tour company vehicle - either way the drivers are insane. Seriously, these drivers are crazy. They pass on blind curves with overloaded vehicles.
I use them all the time but I would not take my baby daughter on them.
If you arrive at 5pm you might exit the airport at 6pm and be on your way at 6:30pm so you will be traveling in the dark. You will arrive in Juan Dolio around 10pm or later.
The worst aspect is sometimes you get Meringue blasted at full volume for the entire length of the journey. I like Meringue but after 4 hours on a distorting stereo system it can sap the will to live.
Take a regular taxi or have someone from DR1 pick you up in their private taxi - especially at that time of night.