I agree with most of what sea1swk is saying but will try to put things into perspective a little differently.

Mah readings are capacity... the larger the capacity, the longer run time you will get, but also get added punch which means your voltage will be less likely to drop under load. The C rating also effects punch, where the higher the C rating, the higher the charge rate the pack can be charged and the pack will tend to increase it's longevity before it starts to show signs of wear which can be measured as "Internal Resistance" (IR), there are some chargers which come with an IR meter to help you measure the health of your packs.

Most packs that I own start out around 1 mΩ and this value will slowly increase over time, I typically retire a pack when any of the cells go past 8 mΩ.

Here is a discharge graph for you to get an idea of C rating combined with Mah (capacity) showing punch over discharge times, sometimes a picture says 1K words

60C-4A is really a 2S shorty pack with 60C rating and 4000mAh, the Y axis is in volts, the X axis is in time

rA is simply multiplying the C rating times capacity as what I refer to "relative amps" in what the pack is rated to handle under max advertised load




Take special note on how the lines cross between the ThrottleWorx and Built-RC packs, the lower capacity ThrottleWorx pack outperforms the Built-RC pack for the first 4-5 min, then they switch where the higher capacity Built-RC pack performs better throughout the duration of the run. This strategy did not hold true for the other 2 packs with significantly higher rA values.

What I have learned for stock racing is that it's generally best to get the largest capacity pack and C rating (highest rA) that you can fit in order to get the best possible performance. With off-road cars, the difference in added punch (acceleration) is better with a higher capacity pack than the negative effect of the added weight, in many cases the added weight can improve performance by allowing a car to jump farther based on Newton's laws of physics. A heavier car will also tend to be more stable in corners making them easier to drive. I do a face palm every time I see a driver with a 3500mAh sub shorty pack with battery weight underneath... just get a larger capacity pack in the first place

As far as putting packs into storage mode, you don't really have to get them to exactly 3.8V/cell, the time you spent after the main is more than enough to reduce the voltage within reason for storage, but if you insist on getting them spot on, then simply drive your car until the LVC kicks in to save time getting your pack to storage charge.