I shoot so little shot shell. It occurred to me I could easily have a lifetime supply of shotgun ammo by keeping shot and powder on hand, plus a few of each size brass shell.
Is there a down side for a low volume shooter?

No one?

I don’t load huge amounts but I always keep components to load target loads just so I dont have to rely on stores to have what I need,

3 years ago I bought my grandson a 410 and didn’t realize how hard it was to find any shells, it was even hard to find a mec loader so I bought the first press and components that I could just to keep him shooting, without loading he wouldn’t have been able to shoot much!

no brass shells are easy to load

How about if I get the expensive ones that are correct diameter inside?

Unless you plan on living to be like 700 years old, just buy a few flats of shells of what you need. You'll come out ahead.

For fun, you can find an old Lee Loader on Ebay. It's slow, but kinda cool for a hobby.