The fact that the amount of drawcalls used by your object has a big influence on its performance is becoming more and more known in the community. A while ago I wrote about the performance I gained when optimizing one of my objects. If this still sounds very new to you, I would advice you to take a look at this article on the FSDeveloper Wiki.
Today I wrote a little tool, based on the code to read MDL objects that I developed for ModelConverterX, that can give you a little more insight in how well your object is optimized. This tool will read your MDL object and then show you some statistics about it. For example the amount of drawcalls and texture vertices that are used in the different LODs of your object.