This a reply from this link:
https://www.reddit.com/r/electronic_cigarette/comments/57wa99/rtas_vs_rdas/
"People are going to say flavor and vapor is better with an RDA compared to an RTA, while in some cases this is true it's not always the case. It really depends on the RDA and RTA you're comparing. I have RTA's that outperform some of my RDA's in comparison to flavor but the RDA in this case will probably produce more vapor and vice versa. I have some RDA's that are more flavorful but have RTA's that will produce more vapor than those RDA's.
What all this really boils down to are a few things. What are you looking for in a device? More vapor? More flavor? A mixture of both? The correlation between flavor/vapor has a lot to do with the amount of airflow as well as a few other things but this is the easiest one to pick out when shopping for something new. More airflow will more often than not equal less flavor but more vapor. Less airflow will produce more flavor but less vapor. There are a few other variants to come into play another being what type of build you'll be throwing into said RDA/RTA. RDA's can be easier to build and wick then most RTA's but I have a few that are just as easy as an RDA. RTA's are best for driving purposes or just filling and vaping away for longer periods of time without worrying about filling up juice but if you don't mind the constant dripping with an RDA then that's not a big deal.
In the end it's really all up to personal preference and what you're looking for in your day to day vape. Let your style of vaping choose what kind of atomizer you look for and not what other's around you are using and you'll have a much better experience with your vape
"
There are definitely cloud chasing RTAs. I only run flavor chasing single coil parallel builds on single 21700 mods though so I only have experience with the flavor chasing single coil ones. I love my Coppervape Skyline though.
I want to get another RTA that's more airy though. I like a RLH but that's pretty damn restrictive. The flavor is as good as my RDAs with the exception of the Hadaly and a few others. The advantage though is that spitback is a lot less likely with an RTA. My parallel builds don't have any spitback in general but if you oversquonk badly it can happen. My suggestion would be try both. Get some that are highly well rated and decide for yourself what you prefer. I basically agree with what's in quotes as far convenience goes.