Pick out which boxes you are interested in.
Ask for a price breakdown, inform each dealer that you will be comparing price, drawer configurations, etc...
Assess your options and make the decision based on what is most important to yourself.
Things like trade in value, wait time, expand-ability (side cabs, risers, topchests), color, and price would be the things I would consider most.
Spending big money on a box is a personal decision. Do not let someone dissuade you from making the choice you are comfortable with. Both boxes you are considering should give you a long service life and give you plenty of bragging rights. I do not think you will be unhappy choosing either.
Good luck. Please give us pictures of your new box when you make the choice.
At my work, most of the popular offerings are represented. I used to have a SO heritage and now have a SO KRSC and CM 26" which take care of my needs well. Having had the opportunity to see both boxes, I would not shy away from either. Thing is my work only has a SO guy so that would probably make my decision for me.