I have auxiliary brake levers on my drop handlebar bikes, precisely to be able to sit upright and see better (over the tops of cars) when cycling in traffic, while still being able to brake.
However, I consider the braking from these levers as being a bit less effective than with flat-bar levers on straight or "sit up and beg" bars and less effective than braking from the main brake levers on drop bars.
My utility bike currently has straight bars (bought originally to do trials before finally deciding on drops for my Thorn touring bike).
I shall probably convert this bike eventually, either to drops or to what I call "sit up and beg" bars, as I am not a great fan of the hand position on straight bars.
The photo shows "sit up and beg" bars on a recently completed bike for visitors to our island flat. On this bike they are set high and fairly close, but can be set up for a more sporty position by using a longer stem fitted lower, or for a very sporty position by inversing the bars "moustache" style as often used on fixies. These bars are fairly narrow at 480 mm.
