3-motor transmissions

Based on a topic brought up in the "Why not shift" thread (http://bit.ly/UgKdrg)

With the new Vex 3-motor, single-speed gearbox, something I've been looking into is why certain teams have or have not used a 3 motor transmission, and the logistics of such.

Here are some of my main concerns:

1) Have you used a 3 motor transmission in the past before?
If no, why not?
If yes, why did you want one? Do you think it was worth the extra work? Did you have any problems? Was it a shifting transmission or a single speed?

2) What kind of motor would you use in the 3rd motor slot? I've heard a lot about teams ditching their 3rd motors due to burning them out too often. How is this caused, and what precautions can be taken to prevent it?

3) What kind of wheels did you use with the 3-motor transmission? Did they work into a strategy used with the 3-motor transmission? Had you had a 2 motor transmission would you have used different wheels? When in the design process did you decide to use a 3-motor transmission?

4) Last but not least, what other advice would you have for a person looking into using a 3-motor transmission?


Thanks!