The Downtube Mini is my daily commuter, so I've lavished it a bit.
So, while the Downtube Mini is a good bargain, some of the components it comes with aren't exactly "good".
First thing that had to go were the stock grips and brakes/levers and I absolutely needed some fenders. Jur's elastomer suspension mod came a few days later, which made the bike SO much better.
When I noticed that the stock headset was shot, and not properly put together in the first place, I went all-out. Not only was the headset shot, but the threading on the steerer was poorly done and the bottom bracket was installed way too tightly. My LBS cleaned up the threads on the steerer and pulled the BB out for me and I was free to work.
I swapped the headset, bottom bracket, crankset, chainguard, sprocket, chainring, seatpost, saddle, and pedals. On top of this, I rebuilt the front wheel around a new hub with radial lacing.
Brake Levers: Shimano Deore
Brakes: Shimano Deore
Headset: Toro Odessey Pro
Bottom Bracket: Race Face ISIS 108mm
Crankset: Truvativ Elita 170mm
Pedals: MKS FD-6 folding pedals
Seatpost: FSA FR-270 420mm 27.2 seatpost
Front hub: Ritchey 24h hub with cartridge bearings
Tires: Schwalbe Big Apple
Fenders: Dahon 16" SKS
Now that the bike is done, it has cost me damn near a Brompton or BF Tikit, but neither of those ships with the Sturmey 8. The DT Mini also has no chain tensioner, which is a perk with no dropped chains.
The only thing left to do is figure out how to carry something on it. I'd love to do something similar to the Dahon Curve or the Brompton on the head-tube, but there are no provisions for it on the Mini. If anyone has ideas for how to carry cargo on the front of the Mini, I'm open to suggestions.
BTW, for those wanting a better seatpost for your Mini, only buy the FSA if you have an inseam of 30 and under. A safer option is the Nitto at 460mm, but at $80, you may have second thoughts.