What are the pros and cons of each?
A Vision Tech base bar and clip-ons is probably just as aerodynamic as the best integrated bars but a lot cheaper.
Be careful when purchasing integrated bars. A group of them were tested in a wind tunnel. Some were very good but one of the most expensive was slower than a basic round bull horn bar and clips. The test is a few years old now, but is available on roadbikereview.com
Sometimes it pays to do your research before droppping down the big coin.
I run a 90mm stem so I can not use most fully integrated aerobars. The other option is to use a semi integrated aerobar like the HED, Oval that do not come with a stem. I personally like to have the option to tilt the aerobars independently of the base bar so I have the HED Flip-lite, Easton Delta Force base bar, Tektro Carbon levers and use a Syntace F99 stem. Total weight of this set up is 745g which is lighter than most integrated units and fully adjustable.
I raced last year on VisionTech integrated aerobars and they were fine, but I reached a point where I decided I wanted to go lower and I just plain couldn’t. As others on this thread have already noted, you have much more flexibility to play with reach, bar angle and the like with independent components. I’ve switched to using a set of Oval clip on bars with a VT base bar and Oval stem. While the bar/basebar may be a hair less sleek than the integrated unit, it’s allowed me to make some position changes to reduce my overall frontal area that I could not make with the integrated setup.
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