I’d be a bit careful with Halo on anything treated with DWR (i.e. Paramo or other waterproofs like GoreTex etc). It’ll be great for your base layery type things.
The violet laundry stuff sounds like it should be OK on stuff with DWR on it.
I should say BTW that I have recently started working at Nikwax so obviously I’d say Nikwax will ultimately give you best results.
Feel free to DM me if you want to know anything more specific and I promise I will give you a balanced answer. Just don’t want you to knacker your kit!