the tape has been causing me issues on my flows, its a pain when it gets a kink in it etc,
That sounds like the tape hasn’t been stretched properly when fitted.
Why the Flow EX’s too? There are other rims in the NoTubes range that are more comparable to the ST rims.
The Mavic rims (ST and SX) are solid and can take some abuse…I sold mine though, due to the poor hubs and spokes that many places don’t stock.
EDIT: The ST’s are supposed to be 1650g…I can’t confirm that and don’t know if that is with the valves. I do know the Flow Ex’s on CK hubs with DT Swiss DB spokes, brass nipples, tape and valves would be about 1900g.
The Arch EX rims would be 180g lighter (90g per rim).
This might be of use too: Stan’s rim comparisons. 😉