As an Armored Cavalry officer, I have some issues with all this.

105mm v. 120mm: You've got to be kidding me that it has as much, if not more, than an Abrams.

It carries less than half the UBL of an Abrams. After the ready rack is expended, you have to expose a soldier to reload the bloody thing.

This is not a replacement to the MBT. It's an enhancement for Stryker units. Comparing the MGS to an Abrams is mixing apples and oranges.