The whole point of a multi-fuel stove is that it gives you options. One fuel may be more suited to colder conditions, another may permit better simmering, one could be the cheapest option, another may be the only fuel available. Aspen 4 is amongst the very best of fuel options for a liquid fuel stove.
Many of us will have managed to fit in a few weeks of backpacking this year and some gear might have been having a rough time of it. Beside cleaning, re-proofing and condition checking, think about including an inspection of the O-rings fitted to gas and multi-fuel stoves.