I only use tell tales sailing uni-rigged off the breeze and then only if I can't go wild. The 430 is not like other uni-rigged cats I've sailed, in that it works best with the traveller centered and the sheet on hard in anything above 5/8ks.
With the kite up I'll need them until I find the best traveller position which goes with a folding spi leading edge.

That's how I'm seeing it presently but things may change as I become more familiar with kiting on a cat.