Testimonials and reviews

(Please note: all reviews are on external websites. Underwater Experiences is not responsible for their content.)


The RB Guardian is an excellent piece of kit. I have been using the Inspiration for just over six-and-a-half years now. The ADV I bought from Bob Howell was the first mod which lended you a hand and gave back time. The RB Guardian is another item that gives you time back: you no longer gaze at your handsets, watching the digits for analysis. The information you require is instant and in your face. Even my buddy—a non-rebreather diver—could see the LEDs and knew everything was OK. And for those individuals who are normally busy underwater and that get easily distracted, you will never forget to change your set point again!

I again put the RB Guardian through its paces at the weekend. Once I calibrated it, I left it on (for ten hours). In the meantime, I did two dives. I know this unit and I are going to get along fine. Thanks for designing such a cool piece of gear!

Norman Woods, Coleraine, N Ireland


Just two words: bloody fantastic!

David Howell (a very happy HUD diver)


I was quite impressed with the accuracy when comparing the lights to PO2 displays, and the speed with which the LEDs responded. It was easy to use and understand, and an additional plus was that other divers with me could quite easily see the status of my unit from the glow and reflection of the lights. For anyone who has found themselves detracted from paying attention to their handsets (or sometimes found it difficult to do so, such as when in a cave, or shooting video) I think it would be a real bonus.

Martin Robson


The system reduces the handsets to gauges to be checked in emergencies only rather than every minute as recommended by APD. As such, it is the primary display. During ascent/decent and during the bottom phase there is no need to look at the handsets, as all valid information is in your face for the whole dive. This is not the case with other HUDs on the market.

Can you do everything on the HUD? No.

Can you safely do the whole dive relying on your HUD to warn you of any errors or danger? Yes.

In my opinion, that is the difference.

I don't find checking handsets every 30 seconds task loading—it's not exactly rocket science! I don't forget to check my handsets, but I might on a given day. I don't lack the discipline to check my hand sets—I am anal about kit prep. maintenance and dive planning...

I just don't want to!

I just want to dive. And a dive involves the freedom and sheer pleasure of weightlessness combined with the spectacle of the wreck, reef, or wall. It should not involve having to check my equipment every 30 seconds. The RB Guardian frees me from this restriction.

Mark Chase


I've been using one of the pre-production HUDs for a good few months now. It has accompanied me on dives ranging from knocking about in the pool to 70m in the Channel, and I find it an excellent tool. I've spent a lot of time on skills and drills trying to catch it out, but it tracks pp02 changes nicely and gives a timely warning of anomalous levels—more timely than the unit's handsets, in fact. The thresholds are such that in the event of either a high or low pp02, the LEDs will indicate long before a warning sounds on the unit. I'm extremely pleased with it, and can't imagine HUDless diving now!

Robin Evans


"So what," you might be thinking, "are the advantages of using a Heads-Up Display?" Firstly, once confidence is gained in the HUD's ability to provide you with accurate information, the process of diving with a rebreather becomes very liberating. A well-known south coast skipper once said he could spot a rebreather diver "a mile off" because they were always looking at their handsets. How right he was!

But with the RB Guardian, pp02 monitoring using a HUD has never been simpler: if anything flashes red, be aware; if all lights are green, enjoy your dive! Multitasking underwater—for example, riding a scooter, photography and even bagging up a porthole—takes your mind off of pp02 monitoring, no matter what anyone tells you. I have done complete dives using the HUD and deliberately never looked at a handset. Now, that's liberating! I can now take that "once in a lifetime" photographic shot without thinking "I wonder what my handsets are saying".

I have tested this HUD at various depths to 100m, checked and tested results at different levels of pp02, and have always found it to be bang on. As a truly independent set of electronics, I feel safe that if the main electronics went down I could still run the rebreather manually in fully closed circuit mode and still be 100 per cent confident that I know my pp02. If you're as serious about your rebreather diving as I am, this HUD is a must!

Jeff Cornish: Darkstar Expedition Team  Transylvania 2002, Tuscania and Andania 2004.


If you have some feedback of your own about the RB Guardian that you wish to share, please let us know.


Back to RB Guardian page.