RIBs are fine - we don't aim to provide as good quality data as a professional survey, but as you can see on this chart The State of Hydrographic Surveying
(from UKHO data) there is a lot of our waters that need better surveying.
Because a normal depth sounder has a much wider beam angle than a depth sounder intended for a professional survey, and is just single beam, we don't need an MRU - the wider beam angle eliminates most effects of changes in heel and trim.
The only drawback with high speed is if the depth sounder loses the bottom echo due to aeration of the transducer. We build up data from multiple passes of an area, so the greater distance between pings at higher speed isn't an issue, as in time other passes will fill in the gaps.
All you need to take part is a GPS and a depth sounder, with NMEA0183 or Seatalk output. We supply a small data logger that is simple to connect up and stores data on a USB memory stick, which you take home at the end of the day and upload the data to our web site.