Also note the level of the discs. If you have multiple discs of the same type (e.g. the Assault Rifle's "Grenade Round") at different levels, you don't have to "work your way up" from lowest to highest. Just use the highest one you have and the rest can be used as fodder.
Or skip the waiting, go to the Personal Shop (pink consoles) and set the search type to discs. Then just scroll through and look for any Level 10 discs, as I believe that's the highest level currently. I've been able to find quite a few in the range of 1,050-2,500 Meseta, which isn't a high price at all to pay for top-level techniques. Grab one of every kind you can find (or would care to use) and just like that every drop of that particular type from here on out can be used as fodder (and if your luck is anything like mine you'll find at least half a dozen or more of these discs for every exploration mission you do).