440 Source distributor question

I have purchased and taken apart both the MSD Pro-Billet, and the 440 Source unit that is supposed to be similar. The reason I had them apart was to lock out the mechanical advance because I am running timing control via fuel injection. Anyway, the build quality is much better on the MSD Pro Billet, especially if you want to do any kind of adjusting or locking out. The 440 source unit looks similar from the outside, but internally, they are not built as robustly. I'm not saying the 440 Source unit is a bad unit - just know that it is not an exact copy of the MSD Pro Billet.