I refill from the Asian butane bottles just as part of my hobby and not to save money or try to get better results.
in the winter when it gets sub zero here in Minneapolis I put the empty's outside and the bottles in hot tap water.
In a few minutes the refill is done.on some old carts the Lindal valve has been used so much it won't work.
this Fall I had a cold morning and the stove was a hard light so I put it under my jacket and that was enough to warm up the butane and after it lit the heat off the burner kept it roaring.
if I went off in really cold winter weather I would take my old multi fuel Optimus 111. stocking up for an emergency I would buy all the best brand new.