[Request for Recommendations] 1U-4U Uninterruptible Power Supplies

I recently stated out loud that my homelab was stable, and now my UPS is posting less than 30 minutes of estimated normal load. What's everyone using as a UPS?

I've been rocking the aptly-named CyberPower OR1500LCDRT2U for the past few years. Should I just replace the cells or upgrade the whole unit?