I strongly recommend you try it.
In the countries it's available, it's very often used to replace Amlodipine in patients who can't tolerate it due to edema. Off the top of my head it worked as well as Amlodipine for BP control, without the edema side effect in over 90% of people who had edema with Amlodipine, Then you consider the other health benefits from opening micro vessels in the kidney and liver, and it's a no brainer.
Keep in mind you need 2x the dose of Cild to get the equivalent BP reduction effect of Amlodipine.
If you're adding it to your current combo, I'd start with 5mg (=2.5mg Amlodipine). If after a couple of weeks all is well, and you want to lower BP further try 10mg.
PCT24 has Cildipidine
5mg 1x10 60¢
10mg 1x10 80¢
20mg 1x10 $1
They're splittable, so I'd get the 10s. That will allow you to try 5mg, but I think it's likely you'll end up using 10mg.