I went back and forth on this a lot myself. Then a buddy put it this way. An electronic logbook IS a paper logbook after you print it out. You sign it the same way you would your old black log from Sportys. As long as you have the original of anything that still would require a signature I think it is fine. You still sign every page when it is printed out. I have blank pages in the very back of my printed out electronic log for endorsements. When I go to annual training I just have them print me out a sticker for my instrument proficiency, Bi-annual review, etc... then put the sticker in the back of the book. I haven't written in a physical log book in about a year and a half.