I'm currently working on building two Brompton clones (Actually done building the first one, and transferring parts to the second frame for now). Two have slightly different dimensions (3sixty one is a copy of old Taiwan Brompton and EasyTi is based on current Brompton) but most parts are compatible.
#1 : 3Sixty m3 chrome plated
3Sixty Cromoly frame/fork/handlepost/rear frame (chrome plated version)
Frame modified for external 2-speed drivetrain
820gr Chinese prebuilt wheelset
7.98kg (as shown above)
#2 : EasyTi full titanium (Left one)
Titanium main frame / handlepost /fork (currently shipping) / rear frame (currently shipping)
780gr Chinese prebuilt wheelset (shipping)
Calculated final weight: 5.85kg
Frankly I always thought Bromptons are overpriced boat anchors but those clones are actually pretty good value, with some tuneup.