Does anyone have advice in regard to selecting C-MED XO position over BGD MEDO?

At this stage in your career, the XO position is the more appropriate option. It will help develop you better for your future Command position and you will have more than enough time and opportunity to serve on a staff.

I think the XO position will give you a broader fund of knowledge and you will likely be more useful in the process. The counterargument is visibility at the strategic level. If you feel ready to put products before the boss and will shine like a new penny while you do, then step up to Brigade. If not, better to be an over-prepared and talented XO. OPORDs ANNEXs and MDMP....vs. Nuts/bolts/getting the job done.

I see somewhat of a tradeoff here, depending on your circumstances.

The XO job should better prepare you for being an effective company commander. However, if the Brigade Commander selects his/her company commanders (which is the case in AD units), and you're looking to command within that brigade, then the medical operations job would give you better visibility with that Brigade Commander (to help you impress him/her and get a command position). So, your circumstances may dictate the best decision for you, and that decision wouldn't be the same for everyone.

Bottom line.....both jobs add value, so do well in whichever job you take and you'll be just fine. Best of luck!