Hi Jug.

I hope to not confuse you more with my answer, I'll try to do it as clear as possible it's 3:40 AM. [sm=tired.gif]

NO, the ESC will not break down if the battery has a given cont number and a high burst, the ESC will handle it. The battery is like a portable storage that hold the power until the ESC ask for it. How much and how fast will release this power with out overheating it's set by the C number that the company give. C = one time the capacity of the battery and the number before it will tell you the discharge rate of the battery by multiplying the mah by the number. For example: a 2100 mah lipo has a C of 2100 so if the rating is 15C cont then the max A ( amp ) will be 31.5A ( 15 x 2100 = 31500 ). Since 1000mah = 1A then 2100mah = 2.100A we do the matt again 15 x 2.100 = 31.5A . The max burst is set for 15 sec this will be 24C once again 24 x 2.100 = 50.4 round it to 50. When you go for setting your system go by the cont rate and not by the burst rate.

Now with the ESC you always can go with the recommended 35A or go at least one bigger than suggested 40A will not hurt, only in weight if you are counting every gram. Now think of it like the gas pedal of a car the more you press it the faster or more power the car get. So the more throttle you give on the Tx the more power it will draw from the battery and pass it to the motor. That’s where the rating come in auction by giving you the maximum amount of Amps that your ESC was set to work without danger of overheating. The same goes for the motor when it received. So going back to the example if you have a 35A ESC the battery will be ok since the cont A will be 31.5A. As long as you don't keep full throttle all the time because the ESC will draw 35A from the lipo and that's more than 31.5A but as long as you do small burst you can go as much as 50A and that’s more than the 35A. Same for the motor receiving it.

Just make sure you have a balance in the system your going to use. If you go with the recommended or bigger ESC that's ok as long as you keep a good throttle management so you don't overamp the system. This number can be affected by a few factors so you have to keep in consideration. One is the prop size like the other members already told you. A bigger prop will find more resistance with the air causing the motor to work harder so it will need more amperage to perform, in return can cause overheat to any or all parts of the system. The second will be cooling, is you don't assure a good flow of air trough the system ( Lipo, ESC, Motor ) it will cause the heat to rise faster specially when the rating is lower or close to the limit, with bigger rating it take longer to heat.

Hope it help.

Fernando