The ONLY way I would run rim clamp brakes is if I also had a coaster brake. There are a lot of posters here on this site that will tell you coaster brakes are a bad idea on a motorized bike. If that is all you have, it is better than no brakes. They heat up too fast and cannot shed heat, cooking the grease & frying the bearings in the process. Rim clamps apply the friction over a much larger area that is able to shed heat away from the bearing or grease, but require more force to equal the same stopping power.
By running both hand brakes & a coaster brake, you have esentially a foot powered emergency brake. For normal stopping you squeeze the handle to slow down & stop, but you also have the option of back pedaling for a panic stop. You don't want to use a coaster all the time, for obvious reasons: It's brutal on the hub & bearings, it can easily lock up in soft sand or gravel, and locking it up can & will wear flat spots on the tire, resulting in a subtle wheel vibe that magnifies at increasing speed. Use it only in emergencies when you need to stop NOW! I would rather pay $50 for a new flame tread tire than a thousand dollar hospital bill, on top of a ruined bike and damages to someone's vehicle.
Servicing a coaster brake is also more labor intensive compared to rim clamps, you have to dismount the wheel & chains just to gain access, disassemble the hub, then there's realigning the wheel properly so the gears won't bind the chain. That can take as much as an hour or more, whereas servicing rim clamp pads is 10 minutes with a single wrench.
Now disc brakes offer a superior solution, they shed heat better, require a fraction of the grip rim clamps need, they are easier to service compared to coasters, and can lock up enough to throw you over the handlebars. The only downside I can report is disc brakes are noisy, mine moans when applied. But that's a small price to pay for the ability to stop on a dime & give you back 6¢ change. I have no experience with drum brakes so I cannot say one way or another.
