I'd recommend Premier electronet over that available from Kencove, especially if you're going for the double-spike option. Premier's is solid steel, while Kencove's is a fiberglass post with a second spike of steel connected with a plastic step panel, which has a terrible tendency to torque in hard and/or rocky soils. Overall construction seems better with Premier's, too. Kencove's works fine, but I prefer Premier.
That said, be sure you really want electronet before making the investment. It has its uses, but in my opinion it's more trouble than it's worth.
I've got a Stafix charger that works great, though I have nothing with which to compare it. Used it for over 4 years nonstop without a hitch. Generally speaking, chargers made in New Zealand are always worth the money. And as mentioned by others, get the biggest you can. Better too much oomph than not
enough.