With a bunch of different hubs available for the Brompton, I thought a comparison would be a good idea:
|Kindernay||Rohloff||Alfine 11||Alfine 8||Enviolo|
|Number of gears||14||14||11||8||n/a||8|
|Lever*||Lever*||Twist||Twist or Thumb|
|Efficiency||Very good||Very good||Good||Medium||Good||Medium|
|Axle||Solid 10mm||Quick release||Solid 10mm||Solid 10mm||Solid 10mm||Solid 13/32″|
Gear ratios are the most common possibilities – with the Rohloff and Kindernay, they are with the smallest possible rear cog and largest Brompton front ring (54t). With the Alfine and Enviolo, it’s 18t/50t. So getting higher gears is possible on the Alfine and Enviolo hubs, more difficult with the Kindernay and Rohloff.
I know it seems a bit odd that the Kindernay has a wider range than the Rohloff but has very similar gear ratios, but it’s because the difference between 18″ and 19″ at the bottom end is a much bigger difference than between 98″ and 100″ at the top end.
Other factors are harder to quantify in a table: In terms of fitting, the Rohloff is easiest – it’s a simple quick release hub (though I usually use an Allen key skewer) and cable fitting is very simple. The Alfine and Enviolo hubs are nutted, so need a spanner to fit, but cabling is pretty simple. The Kindernay is the most complex, with a nutted through axle, and hydraulic shifting that has to be cut and perhaps re-bled to fit.
*A rapid-fire shifter is available, but I strongly recommend the Jtek shifter for the Brompton handlebars.