The Sirius chargers and testers are the best.. PERIOD!!
I've used them since 1995 and haven't had any problems with them.
Just a word of caution with packs older than 3 years. Keep an eye on them.
There's more that can go wrong with old packs than just capacity. I too have
rejuvenated old packs but I check them often. The best authority on batteries
I have ever seen is Red Scholefield. He says after the old packs have come
back to life charge them fully and test the capacity after they have set for 72
hours. If they still check good , they're good. Sirius chargers are good but they
don't work miracles.
You can ask Red any questions you might have about batteries on this forum
under the batteries and chargers section.

tommy s

PS: The Ace Smart Charge is not the same. Piece of crap. Bad copy of the Sirius
with inferior components. Licensed by Sirius to build them but changed the design
without Sirius's permission.