> The issue with this design is the front 3 geared hub. It says it would reduce maintenance needs. The derailleur and chain are often cheaper and require very little maintenance other than oiling and maybe cleaning.
Internally geared hubs are a mature technology and really require even less maintenance than a chain/derailleur combo, being completely enclosed. Also, not every hub needs to be a fancy Rohloff, so even if it needs to be replaced in toto, it's not bank-breaking.
I've found the exact opposite when looking at this in the past. The last time I bothered looking there are sturmey archer designs which have an odd slop in the pedalling, shimano designs (which are ok) and Rohloff (super expensive).
Contrast that to chain, cassette and the entire wheel is probably cost less than a hub. A new chain and cassette can be found at any bike shop and they are inexpensive. The maintenance concerns regarding chains are derailleurs are vastly overstated by the proponents of such hubs.
I have built and repaired my own bicycles since I was a kid. I've found that anything remotely fancy becomes a PITA. There is a reason why most bicycles use Shimano or Shimano compatible kit, it is cheap, available anywhere and reliable.
Internally geared hubs are a mature technology and really require even less maintenance than a chain/derailleur combo, being completely enclosed. Also, not every hub needs to be a fancy Rohloff, so even if it needs to be replaced in toto, it's not bank-breaking.