To the OP:
You can choose not to believe the very sound advice that many here have given you. But why not do a bit of poking around the internet and go to well-respected sites like Trojan (quality battery makers) or others and check for yourself? Yes, your batteries will come back up with a good charging, but they will last just a fraction of the number of cycles you would normally get from them. Taking your batteries down to a 20 percent charge is harmful to your batteries and will severely shorten their life.
But they are your batteries and it is your money, so you can spend it anyway you want.