Yeah, that's one I forgot for MD. The "approved handgun roster" - the state has to review a firearm before they "allow" it to be sold here.
No Hellcats for me, yet.
Also, 10rd limits on paper. Not sure how that would apply to a Hellcat, but I do know that many handguns are sold with factory capacities that exceed 10rds.
LEOs are a little more understanding than the state review board - my "good and substantial" reason is, small business owner (live audio production company; I do concerts). MD rule for the "reason" can be: cash deposits; real estate situations (I also own rentals); and judgement calls by the MSP. At the time of my application process, the three most popular targets were schools, churches, and nightclubs. Soon as I said "concert sound", they looked at me and asked "clubs and bars?". That locked it.
State law is carry "while engaged in the activity of your job, which requires the firearm". No other times, only supposed to carry when engaged in work.
The back of my permit is worded "any business on-site or off, pertaining to" my company. That includes networking, meetings, bank runs, client interviews, etc. I specifically asked that question when my permit was issued, because I don't need to get in trouble for "illegal carrying" here in the Republik of Maryland.
Advice I've been given? "Sound company, eh? Keep a broken speaker in your car." Similar to the advice-meme I've seen that says "if you carry a bat in your car, make sure you also have a glove - your lawyer will thank you!".
And in Maryland, you ARE allowed to carry in an establishment that serves alcohol, as long as you do not partake.