having experienced both, sans-front brake, i would say its way easier stopping on a coaster brake compared to a fixed gear bike. however i still would ride both with a front brake. i dont currently on my coaster brake bike, i dont necessarily feel unsafe riding it, but a front brake is something i do plan on adding in the near future. my fiance's bike is a coaster brake bike and she loves it. a singlespeed mixte. i put a front brake on it but she never uses it. moreso as a backup.

anywho just my 2cents. coaster brake bikes arn't unsafe, i dunno where people are getting that from. pretty much every beach cruiser and kid's bike ive seen have them and they stop fine. albeit have a tendency to skid way easier. but sometimes thats part of the fun