Gas fire recommendation ?

steady__eddie

I need to buy a replacement gas fire for the lounge (5 metres long by 4 metres wide by 8 foot high). The one that's in doesn't appear to be terribly efficient and the central heating although it does the job satisfactorily does leave me gasping for air at times (COPD).
I have been looking at these high efficiency jobs but a visit to a retailer yesterday has left me confused. He said that a 4.4 kw H.E. fire (89% efficient) will not push as much heat out as much heat as a 67% efficient 4.4 kw ordinary one because the glass on the H.E. job prevents the heat from being dissipated in the room.
I had been working on the assumption that if the fuel was used more efficiently then I could use it on a higher setting (and hence be warmer).
Could anyone confirm this please and any recommendations for make/model etc. would be appreciated.