They are good community fish, but they lurk at the top, so if you have a top dwelling betta you're gonna have little movement all around your tank. Also, watch yourself on the snails, some get huge, and they are poopers! I got one yesterday, and all you can see is little brown turds in my sand! I had to pooper scoop my sand:) But really though, ditch the inch rule, majority of people hate it because it doesn't take into effect alot of variables.
I keep getting "ditch the inch rule" and "follow the inch rule". This reminds me of my childhood. If i asked my mum for something, he'd say "ask your mother". And guess what my mum said! "Ask your father!". And my book says to go by "surface area of the tank" rather than volume. So three diffent sides to one arguement. Im confazzled. My filter is suitable for a 20 gallon tank, as well as 10... Does that factor in at all?
Sorry, thought you said you wanted both. Hatchets aren't racist, my silvers get along with my common's. Ditch the 1 inch per gallon rule. It is very basic and should only be used by skinny fish that don't make much waste. Goldfish, for example, are very thick and make more waste than other fish. Also, while 6 neons and 4 cories may not be overstocked, 10 cories and no neons would be. The inch per gallon rule comes after behavior, waste production, and avalaible space.
Just a warning, some bettas find them as a tasty snack. I would get the ghost kind, just because they are 33 cents, and if they do become a snack your not out much. If not you can spend the 2 dollars and be good to go!