If only there were an easy answer to this!
The simplest way to choose is to use our Wood Briquette Finder

Why does our Wood Briquette Finder suggest the products it does?
The size and sort of stove, size of room, how often you light your stove etc., will all have an effect on which is the best briquette for you. When we’re talking to customers in our shop, we always ask them for this informaiton so we can give them the best advice.
Our first question is always, what size is your stove?
A five kilowatt stove is one of the most common, but they can range from about 4kw to 40kw. The advice on our site is mostly tailored to a 5kw – 8kw stove, so if your stove is smaller, you will use less fuel generally. If your stove is larger, it will be a bit greedier.
If you’re not sure what kilowatt your stove is, look at the size of room it’s heating. Is it a big room? Is the stove running radiators, or does it heat a back boiler for hot water? If the answer to any of these is yes, it is likely to be larger than 5kw.
If your stove runs radiators, the chances are it will be a bigger stove – usually more than 10kw. Some of our customers have stoves that are up to 40kw – these are pretty tough to keep running economically and will require a good mix of experience, art and science to get the best out of.

The next thing to consider is, how do you use the stove?
Do you just light it when you come home from work, and let it go out by bedtime? If so, look for quick heat and good burn times.
Do you work from home and need gentle backgorund heat all day? Look for long burning with more moderate heat output.
Do you need it to stay in overnight? Look for long-burning but also experiment with your air flow to maximise burn times.