I have that one too (and the green handled pans shown in the photos, oddly enough) - it's pretty stable on the whole! All I'd say is you want to ensure you lay the gas pipe out smoothly so there aren't any kinks that could cause it to tilt, and of course as with any camping stove it's only as stable as the pan you put on it. The lower center of gravity makes it a lot more stable than the kind that clip directly onto the gas canister; probably the most stable camping stove I've owned aside from the large briefcase-style ones, which are amazing unless you're trying to travel light. More a treat for car-camping than something you want to hike or bike with. The fold-out windbreak that comes with it is pretty shite but that's not the end of the world. Overall, I recommend it highly!
And of course, I would in no way wish to be seen as endorsing the use of a camping stove inside the tent no matter how stable, if you go up in flames it's all on you