Roger has many articles about stoves, read them.
Roger hates Pocket Rocket. The flame pattern is non-optimum.
I have a Pocket Rocket. What I like about it is it's old technology, as in proven. Less likely to have some sort of failure. Until they change the manufacturing process. You can find stoves that weigh 2 ounces instead of the 3 ounces of a Pocket Rocket, like the Gnat?
Regular upright stove is good down to 32 degree F, maybe 25 F. Make sure and use iso-butane below about 40 F. You can use it colder than that but you have to have reflective windscreen or wrap a copper wire around stove and up into flame.
Roger's inverted stove should be really good, see his article. Good at much colder temperatures, better in wind,...