whats the differance and which is better during contest time.

The difference is that they have different protein species and it really depends on your diet as to how each would be more effective than the other.

Personally, I prefer UMP ALLWAYS over MP. MP usually doesn't hold me over like UMP does. I am pretty hungry 20 mins after I use strictly MP. That being said, if I used MP with a handfull of nuts and seeds, that hunger wouldn't come as quick....

Either way, I prefer UMP!

I like to use MP more like an additive. Combining it with something else like 100% Egg or Mass Maker.

I would rather use UMP, too.

I opt for MP personally, but I rarely eat just protein by itself, so I prefer the cleaner protein (less fats/carbs) and then add my own low glycemic carbs to slow down the digestive process. However, if you are doing a protein/fat meal UMP is a good option as its slower digesting and will keep you fuller longer.

Just depends on a) goals and b) how you diet.

Well MP should be used first thing in the morning or right after workout because it has fast digesting proteins...UMP should be used as a meal or right before bed because the protein in UMP is slower digesting...That is the difference