I've been happy with X10, but there are a lot of others here who are proponents of moving on to WiFi based solutions. IMO, if you can control the noise on the system, you should be ok. If you can't control it, then you might want to do something different. Now, when it comes to RF, I've been generally unhappy. I do have some RF motion sensors and some wireless remotes. These usually work ok, but there are times that they don't work at all. It seems when the conditions are rainy and cold (I live in Seattle, so...) the RF range shrinks. I've modified my installation to increase PLC and RF reliability and range and under ideal conditions everything works 99%. When I'm under less than ideal conditions, my reliability is closer to 75% for RF and 95% for PLC.
You may need to consider investing in increasing reliability. It will not be cheap, but will cost less than starting over. But, if you don't want to continue to have X10 issues (read, you'd rather try something not X10), there are threads here that might guide you in what other options are. Sonoff seems to be a very popular solution and not too expensive.