Can I put in a vote for the Tekna T2100. No, not the B or BX but the original brass body T2100. It was a performer at depth though it could stutter at 20 feet or less. I enjoyed mine. Small, light, side exhaust, pneumatic servo operated, what is not to love. And it came with a Mark V clone first stage that was better than the Mark V, better chrome, stainless turret screw too and parts compatible.
That is a (40 yo NIB) Tekna Mark V clone there driving a Jetstream, in many ways so similar to the Tekna T2100:
So by default I guess I am throwing in a vote for the Jetstream because it has a side exhaust, is tilt valve pneumatic servo operated and can flow an awful lot of air when requested to do so.
You cannot herd cats, everyone knows that
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