Going to have to disagree in some areas on this thread. Comparing PROPERLY SELECTED multiple carbs to PROPERLY SELECTED single carbs:
Ease of installation - definate edge to single carb
Cost - definate edge to single carb
Problems (after installation) no difference or a minute edge to single carb
Power - definate edge to multiple carb
Fuel economy - edge to multiple carb
The only way a single carb is going to beat the performance (both power and economy) over multiple carbs (remember - properly selected) is on a single cylinder engine.
The major question becomes: Do you want the look, power, and economy of the multiple unit badly enough to spend the time to do it, or to pay someone else to do it.
Jon.