I've got one of the Deltran 4 pack tenders and it works great. Only issue that cropped up after about a year was one of the banks died, not a big deal as I only use 3 of them anyway.
I give it 1.5 thumbs up but would give 2 if the fourth bank didn't die.
12 Yamaha Super T
11 HD Ultra Limited Sunglo Cherry Red & Merlot