gallien krueger mb200 mb 500 and cx115 advice

Unfortunately GK put the feet on the wrong side. They should be on the short side to give a tall cab and better dispersion. You can rectify with a cheap set of feet or shift the stock ones.

True. I have stacked my CX210 the "tall way" without feet. I gained a little height but not much, since the speakers are arranged diagonally. I didn't notice a difference in sound either, but will probably experiment a bit more.
 
If the 210 runs out of puff in a loud situation, try putting it up on a chair so that you may hear it better. Then add another 210 asap. A vertical stack of 4 tens makes a great little rig for rocking out with unamplified drums.

Unfortunately GK put the feet on the wrong side. They should be on the short side to give a tall cab and better dispersion. You can rectify with a cheap set of feet or shift the stock ones.

I will 100% agree with the fact they should made this a vertical cab, I use mine at home so I just put it on its side but it sits on carpet. Good idea to put another set of rubber feet on. I feel the cab sounds better on its side.