Ah, well we put a Clearview inset stove in last November and it's interesting to compare its performance with the standalone Clearview 500 we also have.
Although they, theoretically, put out nearly the same heat we have found that when the inset is first lit it takes a fair bit longer to feel the heat in the room.
This is because the inset is actually pumping some of the heat into the walls surrounding the stove. The result here is that our entire fireplace heats up over a period of a couple of nights and even when the stove isn't lit you can feel the heat from the fireplace for a couple of days as it's acting like a giant storage heater. So this room is now gone from probably being the 'coolest' in the house (v big room with not enough rads) to being the warmest in the winter.
So when you first light up your inset don't be too disappointed if you don't get instant gratification* - after a few days of evening burning you will def feel the benefits.
*We have two stoves in the house, an inset and a standalone so I can compare the performance of the two. If you have just one stove I'm sure you will be more than happy with the inset - ours has made a huge difference.