optimus 123SVEA 123 stoves = 4,700 BTU'd Optimus 8r, and 99 = 3,300 BTU's. My own experience with both stoves seems to easily show the power difference between them. AsWith so many reviews of the Optimus SVEA 123R and 123, i don’t want to re-hash too much, but some points are worth repeating. Let’s start with something I haven’t noticed