Just an FYI about that charger.

It is a AC/DC style charger that cant do 20 amps on a single channel channel. It has a max limit of 10 amps. Now it doesn't specify if thats per channel or combined but it would be pretty weird if it was a 10 amp combined limit. I've attached the specs page on hitec's website.

X2 AC Pro 2 Port AC/DC Multi-Charger | HITEC RCD USA

You could pick up two of these https://www.amainhobbies.com/isdt-t8...isd-t8/p700372 and a power supply off ebay for about 250 and easly charge your batteries at 5C. BTW 5C on those batteries is 29 amps, which would be an insane number to charge at.

I would definitely suggest looking up how lipo's charge and some of the specifics about how they work. This may help with picking out a charger, figuring out what amps you want to charge at and how many watts it takes to charge at.

IIRC - of all your requirements, you should drop the AC/DC one. The majority of the AC/DC chargers are worthless on AC. Also server power supply can be had on ebay for damn cheap, and there are so many guides online for converting one over to charger duties.