Recommend a gas inset stove

AMO

Hi all,

We currently have an open gas fire:


We're trying to find a high efficiency gas inset stove replacement (basically we need something to fit into the same space ideally).

We thought that this one might be a good one:
Crystal Fires Montana Royale High Efficiency Gas Fire (3 Sided)
http://www.crystalfires.co.uk/index.php/fires/montana
http://www.hotprice.co.uk/crystal-montana-royale-3-sided-gas-fire

It looks contemporary. It's got a 5 year warranty. It's got a high efficiency rating (81%). It's fairly powerful (4.3kW).

We also wanted one that is a Conventional Gas Stove as flueless ones seem to come with concerns from some websites such as this:
http://www.harridgestoves.co.uk/4/faqs-woodburning-multifuel-stoves#4

We have also been told by some installers that as the area around some stoves gets very high, we might not be able to keep our existing frame - certainly multi-fuel stoves have their frames in multiple panel components - not sure if this gas stove will cause us to need to change our existing marble frame.

However, we're not expert in gas stoves.

Anyone have any opinions on this gas stove and whether they can recommend any better alternatives.

Thanks.