Which standalone head units would work with Tacx i.Flow T2270?
The Tacx i-Flow is only compatible with the T2202 head unit for standalone use. 

The T1982 Bushido head unit does not connect in my experience, although I have had Tacx support tell me it should work. 

The T1962 Flow head unit firmware is not compatible withe I-Flow. 

Your best guaranteed option is the T2022.