Cool electronics are happy electronics.
Magnum inverter/chargers, are not cheap.
A 100 CFM computer fan, in comparison, is.
Actually 2 50 cfm fans, one pushing and one pulling would be more effective for less noise.
Look into Noctua NF-f12. Very quiet, ~53 CFM, and only consume 0.05 amps at 12v. 7 year warranty. Many fans will consume double this amperage to move less air at twoce the noise level.
They sell industrial versions that spin faster and are rated against dust and moisture intrusion.
In my opinion, Noctua computer fans are the best available.