If you're doing the job for yourself and you don't care about an insurance discount, don't worry about it. Make your choice based on the prices and features among the three panels.
Not in the least. The M1Gold is one of the best engineered panels on the market. Programming is fairly easy with ELK's software (included free if you buy it from an authorized online dealer). It's also an extremely flexible HA controller.
No.
No.