The Flamingo and Brompton side by side
From this angle, the bikes' size look very similar. Without comparing the bikes side by side, you will not be able to tell that there is a difference. However, as you will see from the pictures below, they are not quite the same!
From the side, you can see that the frame of the black Flamingo is higher than the Brompton. This is mainly due to the rack of the Flamingo, which gives it slightly more clearance from the ground compared to the Brompton. Otherwise, the frame height should be similar.
The seatpost of the Brompton is taller only because a longer non-standard seatpost is used. Otherwise the seatpost should be completely hidden when fully lowered.
Looking down from the top, the biggest difference I can see is the saddle location. Somehow, the seat tube angle seems to be different. Also, the Flamingo seatpost has a setback, which places the saddle further back on the seatpost, whereas the Brompton seatpost is straight up without a setback at the clamp area. This causes the saddle on the Flamingo to be located further back, making it stick out the rear more when folded.
The Flamingo is a little wider, due to its 7 speed Shimano Nexus internal hub and the kickstand.
Close up view of headset and headtube
This is the biggest difference between these two bikes, the height of the bikes when folded. The Flamingo headtube is already located higher than the Brompton because the frame is higher up. Also, the handlepost clamp for the Flamingo is located about 2 inches above the headset, as compared to the Brompton handlepost clamp which is located directly above the headset. This causes the overall folded height of the Flamingo to be higher than the Brompton.
As can be seen from the pictures, the Brompton is still the champion when it comes to folded size. From what I measure, the folded Flamingo is about 65cm X 65cm X 33cm when folded. The Brompton seems to be about 3 to 5 cm shorter in all dimensions.
Other Major Differences between Brompton and Flamingo:
1) Flamingo uses an integrated headset, Brompton uses a traditional threaded headset
2) Flamingo uses V-brakes, Brompton uses their proprietary bottom-pull Caliper brakes
3) Flamingo has internal cable routing, Brompton has external cable routing
4) Flamingo uses a simple metal clip to hold onto the rear triangle, Brompton uses a more sophisticated rear frame clip that hooks on automatically to hold onto the rear triangle
5) Flamingo has a wider rear triangle for the internal hub, Brompton has a narrow rear triangle for a super compact fold
If you absolutely need a super compact fold, the Brompton is the one for you. There is no folding bike that folds as well and ride as well at the same time. On the other hand, if you like the folding of the Brompton, but don't mind a slightly larger package, and you are on a tighter budget, the Flamingo would probably be suitable for you!