Over the 5 years that I've been vaping I have always heard the debate between using a RDA and a sub-ohm tank. The simple way to look at it is that a sub-ohm tank setup is always going to be easier to use but the flavor may not be as good. On the other hand when using a RDA (rebuildable dripping atomizer) they are a little more labor intensive to use but offer the best overall flavor.
Many will argue that using a RDA is the only way to truly experience the most from the flavor from any given juice, which I can agree with to a degree. I have also found that sub-ohm tank technology has moved ahead by leaps and bounds in the past few years. For example the new Aspire Cleito tanks such as the Cleito 120 and the Cleito EXO have a resistance of .16 ohms and can be run at 100 watts or better. With that being said the vapor production is very high, and with a higher production of vapor comes better flavor and a more satisfying puff.
On the other side of the coin when using a RDA you are in total control of the resistance of coils you want to use. I personally use homemade fused clapton wires. I use Youde 26g kanthal A1 in parallel with a Youde 38g kanthal A1 wrapping. The idea being that by fusing and wrapping the wire itself makes for a greater surface area for the juice to vaporise off of when the coil is heated. With a RDA setup the costs are a little cheaper as well, simply because the only materials that are needed are coils, which Youde offers a wide variety, and Japanese organic cotton. Sub-ohm tanks require the purchasing of pre-made coils.
In conclusion I will say I use both setups. When I'm at home and relaxing or while at work at Vape Dojo Gambrills I will use my RDA because I'm not worried about having to dripping liquid on the cotton and being distracted by other things. When I'm on the go such as driving, shopping, or just out and about I will use a sub-ohm tank. In my opinion they both have their advantages and disadvantages. Which one is better is always going to be subjective. Always use a setup that is good and works best for you and the situation.