The BEST option is what works for YOU.

I will not argue or debate with anybody who has a system that is, or has been working for them. I can only say what I am using successfully.

I have used lights, and under tank heat. I personally don't care for lights and as soon as I was using high quality plastic enclosures for all of the snake here they were out!

I use Pro-Products RHPs and have them set up the way the manufacturer advised. (Probe on cool side floor level) I have had zero issues and find about a 10 degree difference between warm and cool sides.

No matter what you use, the thermostat makes the system IMO. Even with lights, the Herpstat line worked like a charm.

I do the same as GoingPostal, I also heat the room with a space heater. It is a very large water heat unit. I don't even know if they are made any longer.

I think if you use quality products your chances of anything going wrong are minimal. I don't follow house fire reports, but I don't hear any stories on the news stating "The fire started in a reptile room".

I love the RHPs and find them easy to use once installed.

Using both will never hurt if needed in your situation.

Find your method and go for it!