I have some 44cm flared drop bars (probably around 40cm wide at the tops). For reference, I prefer 40-42cm non flared bars on my road bike. I am not that wide, so the choice may be difference for someone wider in legs. I think you will need to go a little wider than what you would run on a DF bike since you need space for your knees to freely move within the drop bars. I have about 5-10mm clearance to each drop bar with my knees in my normal pedal cycle. Another thing to note is that short cranks will improve the clearance as it keeps knees lower at high point of pedal cycle. I run 155mm cranks.
My V20 44cm bars have about 5cm cut off the ends. I like this much better than the stock very wide bars. It is much better for going through narrow spaces (like bollards), and is more aero. It took a few rides to get used to as you have to put a little more arm effort in on hard sprints and in general for the same stability. Turning tight corners can be a challenge as the bottom of the bars digs into my hips on very short radius corners done at walking pace. But the rest of the time they are great, and I am very happy with the arm position while riding (I rid on the drops with my arms low) which is comfortable and aero.
There seems to be a split on here in terms of some V20 riders preferring higher arms with the arms parallel at shoulder height with a bull horn bar or on the hoods with drop bars, and some V20 riders preferring lower arms with forearm beside torso and elbows bent to a low hand position on the drops. I am the latter, but it seems both options give good speed. If you are like me, the narrower the bars, the less frontal area as you bring them inside your torso shadow (well the torso in the hands shadow!!).
I would recommend it, but not for a beginner. More as an upgrade once someone has mastered the V20 MBB.
This may give some idea of my position.... I don;t have many pics of me riding, so may not be the best photo:
www.strava.com
