Not only are commercial MIDGE stoves a waste of money but they also go against the spirit of wood gasification. Self-reliance is the key to wood gasification, the ability to provide for yourself and for others in times of hardship.
If there was an energy crisis then popping down to the shop for a MIDGE stove is not an option. There won't be any. Nor will there be an Internet for you to purchase one on either.
Another reason for not buying a commercial MIDGE stove is that for some reason they come with an integral battery operated fan to produce a stronger draught. The battery operated fan also goes against the spirit of wood gasification. Where are you going to get batteries from in an emergency?
A well-built gasifier simply doesn't need a forced draught. I have boiled water and cooked meals on my MIDGE stove. That is all they are meant to do and a handmade one does the job perfectly.
Read the plans. Find some cans. Make gas!
MIDGE stove plans - The Complete MIDGE (pdf)