If you’re looking to grab the JBL Xtreme 4, this is the exact one I tested and talked about in the video. I picked mine up on sale (about $120 off), and at that kind of price it was a no-brainer for the battery upgrades, solid build, and Auracast connectivity to PartyBox speakers.
Pros
+Big battery upgrade with strong real-world runtime at normal listening levels
+Swappable battery support (same battery as PartyBox 320)
+IP67 water/dustproof and it floats
+Gets loud for the size with good clarity in the 50–80% volume range
+Auracast connectivity to compatible JBL PartyBox speakers
+Sturdier base than older Xtreme models
Cons
-No 3.5mm aux jack
-No USB-A port
-Bluetooth latency can be an issue for videos
-Sound quality drops off noticeably above ~80% volume