Which one gets your vote for the best high efficiency inset living flame gas fire

[wetdrip]

Guys, Soon, I'm going to purchase this item here:
FIREPLACE SURROUND IN PORTUGUESE LIMESTONE 54" ROKFD | eBay

I'd like to set it off with a nice open living flame, high efficiency inset gas fire.I have a chimney.
So my question is: In your opinion which is the very best High Efficiency gas firefor the job?

 

[diamondgas]

Is there such a thing as a "high efficiency" living flame inset? I'd google it and find one you fancy ... I just did and found fires reportedly up to 90% ... I wouldn't have a clue as to how good they were?