The main difference I see between perlite and vermiculite is the shape of the granules. Perlite is usually round, where as vermiculite is angular, with many different facets. So naturally the vermiculite creates more places for air and water in the soil.

You could also consider a very angular sand like builder's sand or paver sand. It's also angular instead of round. Most people only think of beach sand or play sand when they think of sand but beach sand is very rounded and smooth to the feel where builders and is very coarse and rough.

I will probably mix in some compost and sand to my regular soil to get to a good soil state when I make my beds this month.

Do whatever you like. Opinions vary widely on this subject, and mine are no exception. I went traditional Mel's and would do it again. I still like vermiculite and use only Canadian P. But Mel even says go 100% compost for areas where you can't obtain the other components.

Good luck with whatever you choose.

Here is a link that might be useful: Sinfonian's garden adventure

i found vermiculite for $9.95 3cuft bag at menards [menards is kinda like home depot] but it was in the home insulation department not the garden center. a local garden store had same size bag for $25. i emailed the manufactuer and asked about the vermiculite they replied the vermiculite was the same material they used for garden use, just in a different bag
the name is sun gro horticulture inc. seneca il 61360