I think those two regulator choices are GOOD regulator choices. To make it EXCELLENT, I would add the HOG regulators.
I dive these expensive Poseidon regs because I live in Minnesota and I like the side exhaust of bubbles. Michael Ranoine(sp?) used to service the regs for the US Navy. He told me that he has never seen or heard of a Jetstream failure. As for servicing, there's probably less of a chance a your local dive shop will service Poseidon than some more remote exotic location-like where you're at you lucky diver!. Poseidon does not have a large footprint in the US compared to Scubapro and/or Aqualung.
I have an Apeks TX50 that was used by my ex. I used it once and can't remember a thing about it. I think that's a good review for a regulator. But new Apeks tend to be expensive...as do most regulators. You can get an Apeks serviced almost anywhere.
I hear only GREAT things about the HOG regulators. They are inexpensive, and have 5 HP ports-good for twin set ups. They also make a first stage that does NOT have a swivel and has 4 HP ports.
The major advantage of Poseidon is their cold weather performance and the breathing of the Jetstream and Extreme at depth. The Cyklon are supposed to be bulletproof. But mine seemed to get more gunked up and faster than my Jetstream. There is just so little to go wrong on a Jetstream second stage-just a pilot valve. The Cyklon has a uch more complicated second stage relative to the Jetstream.
The only drawback to the Jetstream, I believe, is that you need the special hose to prevent overinlation in case there is a first stage failure. In other words, you can't just borrow a hose from a friend if your Jetstream hose has failed. The connection is non-standard on the Jetstream anyways.
so, say HELLO to my little friend, the Poseidon Extreme!!! Over pressure valve IN the first stage AND the second stage has a standard port sizing!!!
I bought my Jetstream and Apeks regs from
Online dive shop, buy online diving, snorkeling & swimming equipment when the dollar was strong against the peso. I bought A LOT of dive gear then and Scubastore was wonderful.
Good Luck. Can't "go wrong" withy either manufacturer.