I first got a hailea one (h150) and it was easy to use, relatively quiet, and worked so well I got another hailea one (h500) when I found I needed a larger one. My tank is less than 100l.
It is not so much the size of your rez that counts (although it still counts), more the number of lights putting power into that liquid which you need to remove and airflow.
The better insulated the tank (and buckets) and the fewer lights, the smaller the chiller you need. Conversely, if your system has more lights and more of that heat can enter your nutrient solution, the larger the chiller you will need.
You will also need to think about airflow.
If you pull heat from your solution then dump that heat right on top of your solution you will not lose heat overall from the system, the heat will just flow back into your solution and then you will have a vicious cycle of heating going on and your chiller will just not cope.
What you need to do is you pull cold air in from outside if possible which can refresh the air around your chiller then be exhausted somewhere. Barring this then put the output from your chiller so the exhaust fan from your room takes the heat away.
What you must make sure of is that the waste air does not get recirculated or it will just get too hot and then your chiller will be on 100% of the time and also unable to chill your solution. If this is the situation your solution can end up warmer than if you had no chiller.
I ended up drilling a couple of 22mm holes in the wall and putting the chiller on the other side of it. Keeps the kitchen comfy even in winter.