I have looked at the M P & S. I don't like the look of the P bars and am drawn to the flat bar S.
The P bar is amazing for touring, but let's be honest, it looks a bit outlandish and disproportionate for the Brompton.
The S bar looks sleek and is suitable for low riding, quick "A to B" style. Beware though, as it isn't compatible with the large touring bag. There is however a brilliant new bag this year which you should consider purchasing, as the quick-release luggage block is really one of the Brompton's strong points.
The M bar allows for a more comfortable position and is compatible with the mighty touring bag (its successor is coming out soon by the way, we can expect something even better !).
The rear rack adds weight and breaks the sleek looks, but it makes the Brommie really stable in "parked" mode (folded or semi-folded). With it, you can easily roll the bike just like a trolley (using the Eazy-Wheel kit or your own roller-blade wheels). I often use my Brompton as a shopping trolley, with the touring bag wide open...this way, I don't even have to park the bike outside, it stays with me all the time
Of course, the rear rack is also great if you intend to carry things.
Gears: 2, 3, or 6. Well, I love the 6-speed option (which is a 3-speed hub coupled with a custom 2-speed derailleur), but it really depends on your usage pattern. The new BWR (Brompton Wide Range) gear hub offers an even better choice of gears. There are after market mods, such as a Schlumpf drive (expensive) or a custom-fitted crank gear with fewer teeth.
As for the Titanium bits...I personally think that they are a waste of money, but then, I am neither wealthy not interested in lightweight purism.
My Brompton is a M6R+: M handlebar, 6 speeds, rear Rack, and the "plus" is for the dynamo lights (the rear LED light actually contains a condenser that keeps it on for a few minutes after stopping pedaling). Again, it adds some weight and cables, but it must admit it is quite a nice addition to my battery-powered front light. The new Brompton models come with a re-designed front hub dynamo, so double-check before you buy, otherwise you will be wasting money (when you install your Tongxin).
Although I have the renowned Schwalbe Marathon Plus tyres, I hear good things about the Brompton-branded Kevlar-lined ones.
The brakes have improved over the years, but I would recommend switching to Kool-Stop Salmon pads, at least at the front. They are great ! (I am using the black/pink mixed compound)
The new "handle-saddle" is pretty good, but as usual many prefer to replace it with a Brooks or anything to suit personal taste. I am using an aftermarket saddle with a standard clip. The Brompton Pentaclip is a fantastic little option, as it enables fine-tuning the saddle adjustment.
The extended seat post is a must for normal-height/tall people, unless you like the security of reaching the ground with the flat of your feet (some riders do). I much prefer using the tip of my feet to apply force on the pedals, and I don't mind the extra effort required to keep the bike stable at stopping junctions. There is also an extended seat post that collapses, which helps keeping the overall dimensions small when folded. I have no personal experience with it.
Aftermarket handlebar grips and bar-ends are really a must, and I can thoroughly recommend the ones I am using (you will need to modify the handlebar control layout when you install the Tongxin, so you might as well consider grips that can be easily modified). See here for my review:
Review, Photos of Brompton with BBB Ergoset Handlebar Grips + Bar ends - Bike Forums
In terms of gears I want more than one but even with the S2L I think I would want more gears so that would be custom order I guess.
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I plan to buy it on the cycle to work scheme and later fit a Tongxin to it
Once the motor is on, you can ride nearly all the time in top gear ! The 6-gear Brommie offers a higher gear and a lower cadence, which I like with my Bafang. I actually do use the other 6 gears, even down to the lower one, because of the steep local hills that require a higher cadence (well, it's just my style of riding, as I don't like to rely solely on the motor's assistance).
Having tried the Bafang with a 3-speed Sturmey Archer (on my Merc), I can safely say that 3 speeds is enough with assistance...just pray that your battery never runs flat
You should register on the Yahoo BromptonTalk mailing-list, as there are lots of knowledgeable owners there. It's available to registered-users only, as opposed to open communities like Bikes-Forums.net, etc... I think it's a shame, but that's the way it is.
Let us know how it goes !
Cheers, Daniel
Bonus photos:
