[Q]Efficiency of electroporation of ssDNA vs dsDNA

[Kah-Tong, Seow]

Could someone please refer me to some references which compare
the efficiencies of electroporating ssDNA (e.g. M13) and dsDNA plasmid
 into E. coli. 

For the electroporation of ssDNA (M13), is there a possibility of the
 cell repairing a linear single strand M13 plasmid 
(circularizes it and then convert it to RF form)

Any advice will be appreciated. Thank you.

Kah-Tong, Seow