I upgraded my Axis with TWO 6v 220 amp AGM's last summer. The Full River AGM's will just fit under the steps with no problem (very tight but fit) and are awesome.
I been using the OEM converter every since and it has done fine. But its a single stage and they are known for boiling the batteries so I DONT plug in my RV but once every other week and ony for 24 hours at a time (luckly my indoor storage unit is 3 miles from my house and and has power). This is enough to fully charge them and since the AGM dont loose juice like lead acid im charging much less.
But at a camp ground (or long trip with Genny running for AC) I dont want to forget to flip the converter breaker on or off every day / trip (so I dont over charge).
Luckily Santa brought me the PD 4655 converter!
If its warms up some I might install this weekend (or next) and I will post pictures.
Its a smart charger and they advertize they wont boil the batteries.
Its also a 55 amp hour charger (converter).
2017 Axis / 25.4: Big Foot Levelers, Aims 1200 Watt inverter, Ceramic Window Tint, Full River AGM 6V batteries, Front Hellwig Sway bar / Rear Track Arm, Safe T Plus Steering Stabilizer, PD 4655 converter, Hard Wired Surge Guard, WEboost + WiFi Ranger, LED Headlights/Driving lights, Fresh water surge tank, Black Tank Tornado flush, 4999 zip ties.