I'd reccomend looking for a cheaper pump as well, just to have incase your primary breaks. An old trracer or nelson is always nice to have. Maybe even a Splatmaster, you can use it as a secondary.
For me it's partly paint savings, since 140$ per case isn't fun, but the entry is only 5$ with air. So, with a pump 25$ will get me in with 200 balls, it can last me all day.
It's also more enjoyable in my experience, with the eliminations being more satisfying since it was done with one or two balls, not a rope of 10.