The survey asked users to make a broad-brush estimate how much time they have spent using G4beamline, including all design and analysis for which G4beamline was an essential tool. 34 users responded, of which 8 reported for groups rather than individually.
Total estimated usage:56 FTE-years
Average time using G4beamline:3.1 years

Estimating an FTE-year to cost $200k, and subtracting the usage funded by SBIR or STTR grants, this represents at least $8 Million in Phase III funding by the G4beamline user community.

As can be expected, all of the current, upcoming, or proposed muon experiments are represented: Mu2E, Muon g-2, MICE, MEG, PRISM/PRIME, COMET, MuSiC. Neutrino experiments and proposals are also well represented, as is the Muon Accelerator Program at Fermilab. In addition, the Fermilab test beam and several hadronic experiments are also using G4beamline for design work and background studies. Most of the major particle physics laboratories are included: FNAL, BNL, JLab, SLAC, CERN, RAL, PSI, TRIUMF, KEK, INFN, LANL. Unsurprisingly, Muons, Inc. was the largest single user of G4beamline, followed by MAP, Mu2E, and MICE. G4beamline was cited as essential for one masters thesis and two Ph.D. theses.

Some interesting quotes:
• "It is an absolutely central part of our software suite. The standard GEANT4 tools and our framework are unwieldy for making estimates and getting rough answers for refinement, and without G4Bl we would be lost." — Bob Bernstein, co-spokesperson, Mu2E
• "Given how difficult other software is to use, G4Beamline probably saved me a factor of 2 or more in time to get the information we needed for our research." — Tom Schwarz
• "After using G4BL for more than 2 years it remains my favourite simulation program, even though I have learnt others as well. I prefer G4BL because it is very easy to use and it is easy to debug the files." — Ole Hansen
• "The simple command language interface has made it possible for undergraduates to use it without much training in GEANT4. It is a very useful tool and may be the best available for exploring beam lines and backgrounds. Amazed as to how easy it was to get something working." — Lucien Cremaldi
• "Nice handy tool. To do the problems I am working on would be almost impossible without the aid of such a package." — Doug Jensen
• "This is the first time that such a comprehensive and powerful simulation toolkit (Geant4) has been adapted and streamlined for the use of accelerator physicists, and I think it points the way to the future of simulation studies in our field." — Frederick Jones
• "There are certain problems where G4beamline is not only convenient but often the only well-established tool." — Vasiliy Morozov
• “G4beamline is the only accelerator physics code that can estimate backgrounds.” – (Anon.)
• "G4beamline is open source and organized in such a way that it can be straightforwardly extended by even not a very experienced code developer." — Vasiliy Morozov
• "Our group has had great response to improvements we have suggested so far." - Mary Convery
• "G4beamline is essential for reliable modeling and tracking of secondaries produced from primary beam collisions with the beam chamber walls." — Robert Macek
• "Love using it as an alternative to wrangling with GEANT4 [...]. It's such a time saver and good for teaching and getting students started on simulation for the first time." — (Anon.)
• "I like the way it "just works" - no complicated installation, no mucking about with awkward input formats, easy to set up a lattice and run a beam through." — Chris Rogers