The State Board is authorized to approve the experimental use of voting or counting systems and ballots for the purpose of casting and counting absentee ballots in one or more counties and cities designated by the Board (i) that have established central absentee voter election districts and (ii) whose electoral board and general registrar submit to the Board for approval a plan for the use of such system and ballots. The Board is also authorized to approve the experimental use of voting or counting systems and ballots in one or more precincts in any county or city whose electoral board and general registrar submit to the Board for approval a plan for such use. The use of such systems and ballots at an election shall be valid for all purposes.