I would like to chime in here.
I have the Robart electric retracts in my T/F FW190 have had them for for well over a year and no problems.
I also have them on my T/F corsair for about a year and again no problems. Also have a set in a Holman 86" Hellcat.
I was told by Mitch at D&L that I could run them off my receiver because they do not use much power to make them work, I was apprehensive thinking will you know.. But after flying around 3 to 4 flights they only used around 80mh from the LIFE 2100 battery. Well I was impressed.
Mitch knows his stuff.
I have a Yellow P47 and am considering converting them to electric. No compressor no leaks etc
This is just my two cents worth
Phillco