Question Changing water cooling unit - - - can't decide which to get ?

I assume you are aware that you do not actually need water cooling for a 5800x3d. Most the better aircoolers easily keep the heat under control. Most aircoolers can keep a high end intel chips cool as long as you do not go crazy with the power limits.

Which water cooler you buy in this case is going to be mostly which you like the appearance of. When you compare the actual cooling ability there are not huge difference. They all will have no issues cooling your cpu.
 
You will have no trouble finding reviews of air coolers and many even compare them to water coolers. There are many on this site but I would check a few sites since they do not all test the same way.

What you will find is air coolers have greatly improved in performance over the last few years and have gotten as good as water coolers of similar total size radiators.

The air coolers are a fraction of the cost and pretty much will never fail, even the very best water cooling will lose water over time and get build up that reduces water flow.

You really should only use water cooling if you can not use air cooling.

Of course there are those that use water cool just for the appearance, no way to say which is better in those cases since it depends on what the person likes.