You're talking about the tubular grates, correct?

Yeah, they work.

But they work best with a set of glass doors designed to go with that specific grate heater.

The biggest drawback to fireplaces is that they often suck more heat out of the house than they provide. That's the nature of the chimney effect.

By fitting glass doors, providing for controlled combustion air (best is adjustable vents in the firebox), and using the heater grate you can actually recover a fair amount of heat.

Of course, the very best thing is a fireplace insert, essentially a sealed stove with the blowers.

Far more expensive, but far more efficient.

My Aunt and Uncle have a 2,000 square foot ranch in Central Pennsylvania. They burned about $18 of heating oil last year. All the rest of their heat came from the fireplace insert with the blower.