I've been toying with the idea of getting a Brompton for a while, but I simply cannot make up my mind as to which model to go for (apart from the current predicament of what's available at all ). I'm 179 cm tall and my legs are somewhat shorter, so on my regular road and mountain bikes I ride with a saddle height of 71.5 cm (top of the saddle to center of crank set). I'm used to a sportier position (road and mtb) and I was almost sure that the S-type bar would fit me the best (lower bar and increased reach due to the forward angle of the S-stem), whereas the M-bar would put me in a too upright position (i.e. bar grips would be higher than the saddle). However, I have tested both bar types and found the M-bar quite ok (not as sporty as I'm used to, but really not that bad at all). On the other hand, I was surprised that on the S-bar Brompton I found myself in a rather too cramped position: while the lower bar position is certainly closer to my setup on the road and mountain bikes I'm used to, somehow the reach seemed too short (i.e. I felt too hunched) and I was missing the more stretched out forward position from my other bikes. For some reason, I did not feel this so much on the M-bar Brompton, even though it has a shorter reach and higher stack on paper.
Another counterintuitive issue that bugs me: I have read that by placing more weight on the front wheel (i.e. forcing one to lean forward more) the S-bar is better at alleviating the twitchy steering that Bromptons are notorious for. Again, I felt that the M-bar was less twitchy (in spite of having less weight on the front wheel), while the S-bar felt rather nervous. To be honest, I spent far less time on the S-bar and the S-bar test bike I rode had Kojak tires, while the M-bar had the stock Marathon Racers, so that might have been due in part to the slicker Kojaks too. And with a longer test ride, I may have become more used to the S-bar, but I'm not sure.
So, all in all, what's the general consensus about the handlebar choice for average height, sporty riders looking for a ride experience closer to regular bikes? Am I wrong, in fact, and is the S-bar twitchier than the M-bar or the other way around?