Tusa RS-520 Vs the Mares Prestige 12 regulator

[argentlion]

I would like what ever input you guys might have. I am looking at a Tusa RS-520 and the Mares Prestige 12 regulator as my first reg. I have no exposure to Tusa gear at all, I know Mares tends to make a solid product. Which do you guys think I should go with?

 

[LeadTurn_SD]

I'm not familiar with the Tusa, but can comment on the Mares MR-12 (have 3 of them, and 2 MR-22 Abyss regs).

The MR-12 is a well-established, simple, rugged design that has been around for a long time. It is now Mares' "low-end" balanced diaphragm regulator (price-wise), but this does not make it a low end regulator. The Prestige 2nd on the other hand is newer, and I don't have any experience at all with it. Mares typically uses a classic, non-adjustable "unbalanced" downstream 2nd stage, and from what I've seen (pictures only) the Prestige seems to follow this design pattern. Some (mistakenly I think) see this simpler 2nd stage design as somehow inferior to adjustable 2nds, but really this just depends on the overall design of the 2nd stage, and a lot depends on proper "tuning" of the 2nd stage.

Best wishes.

 

[Greg Barlow]

I am a big fan of the MR12 first stage. The Prestige is an unbalanced second stage, and like the other Mares models, uses the VAD (vortex assisted design) to create venturi assist.

The Mares regs are very reliable, and the majority of the line meets the US Navy "Class A" requirements. In simple terms that means that a diver breathing at the very heavy rate of 25 breaths per minute (with deep inhalations/exhalations) would have more than enough air at 198' and with a cylinder pressure of 1,500psi. Regs meeting this criteria need to display a complete breathing cycle that has an energy expenditure of less than 1.4 j/l. To clarify the standard even more, a well trained athlete running a fast 800m race would be breathing at about the same level.

Another benefit to Mares regs is that they are easy to service.

Greg Barlow
Former Science Editor for Rodale's Scuba Diving Magazine