Sparking during electroporation of plasmid DNA into bacterial cells
In my experience the elution buffer does not matter (both for E.coli and Mycobacteria). I have heard this before from co-workers, but it usually is based on superstition or anecdotal evidence. I have compared water/EB elution and never saw a difference in sparking (in fact, I usually get slightly more colonies with EB).

When I get arcing (sparks), it's usually because I did not wash enough, have bubbles or have to many bacteria. Arcing is a collapse of resistance.