if you can choose which one, I would choose Janssen. Just one shot needed, no strange side effeccts as far as we know. Really handy. Also called Johnson and Johnson.
no, ideaal certainly not. Only Pfizer and Moderna 3-4 weeks apart. Astrazeneca is a different vaccin that needs longer to develop before the second dose.
They need to be taken 12 weeks apart, right? So are you staying in Thailand? Then I would try to find out closer to the second date, things change so quickly.
I will be getting the Astrazeneca, no choice yet in the Netherlands, but would have liked the Janssen vaccin, developed and first producer in the Netherlands, also called Johnson &Johnson. And maybe do more research on the other vaccins we used to get but don't bother anymore. Some might need a booster.