If you were diving gauges would you feel you need a backup set?
No one has ever presented evidence that gauges are more reliable that computers that are properly maintained.
Pressure gauges can become inaccurate without notice and can read higher than actual pressures. For obvious reasons that can be an extreme hazzard. Pressure transducers are far less likely to exhibit this type of failure. Generally when they fail it is a total failure and you will accend immediately. This is less hazardous than the inaccurate reading of a mechanical gauge.
I would think although more costly a better backup would be a second computer and transmitter.
As for electrical interference from strobes this should not be a problem to a modern wireless computer. It is a proximity sensetive effect(you'd have to be close to the strobe) it is only temporary (when the strobe fires) and would not hinder a dive since the computer should reestablish it's sync within seconds after the strobe fires. It only effects the pressure measurement during that polling cycle and the computer would calulate everything else based on time and depth and then figure in bottle pressure based figures as it gets its next data from the transmitter. If it doesn't receive data within a reasonable amount of time (say 1 minute) it would be considered a failure and for safety you would be aborting your dive with your buddy there to assist with the safety stop and in case of an out of air situation.
No one has ever presented evidence that gauges are more reliable that computers that are properly maintained.
Pressure gauges can become inaccurate without notice and can read higher than actual pressures. For obvious reasons that can be an extreme hazzard. Pressure transducers are far less likely to exhibit this type of failure. Generally when they fail it is a total failure and you will accend immediately. This is less hazardous than the inaccurate reading of a mechanical gauge.
I would think although more costly a better backup would be a second computer and transmitter.
As for electrical interference from strobes this should not be a problem to a modern wireless computer. It is a proximity sensetive effect(you'd have to be close to the strobe) it is only temporary (when the strobe fires) and would not hinder a dive since the computer should reestablish it's sync within seconds after the strobe fires. It only effects the pressure measurement during that polling cycle and the computer would calulate everything else based on time and depth and then figure in bottle pressure based figures as it gets its next data from the transmitter. If it doesn't receive data within a reasonable amount of time (say 1 minute) it would be considered a failure and for safety you would be aborting your dive with your buddy there to assist with the safety stop and in case of an out of air situation.