Honestly, dont even gamble with third-party stuff for a high-stakes wedding in Montana. You need the weather sealing to be 100% legit if it starts pouring during the vows. I have been using the Panasonic DMW-BG1 Battery Grip for Lumix S5II S5IIX for about six months now and it is absolutely fantastic! The build quality is top-tier and it perfectly matches the body texture. One thing people miss is that the S5II has those internal fans for cooling... cheap grips often block airflow or dont have the right gaskets, which is a total nightmare if youre shooting long video sequences during the ceremony. Ngl, the reliability is worth every penny. The circuitry in the OEM model is specifically designed to handle the power draw of the phase-detect autofocus system without causing heat spikes. I had a knockoff once for my old G9 and the vertical joystick felt mushy and would randomly disconnect... total vibe killer when youre trying to nail focus. The Panasonic DMW-BG1 Battery Grip feels like a natural extension of the camera and the weight balance is amazing when youre rocking a heavy lens like the Panasonic Lumix S PRO 24-70mm f/2.8 Lens. Seriously, keep hunting for that OEM version because nothing else is gonna survive a rainy Montana weekend with the same reliability! Its better to pay for the peace of mind...

ngl i was in the same boat a few months back. I ended up picking up the JJC DMW-BG1 Battery Grip for Panasonic S5II as a temporary fix and honestly i have been pretty satisfied with how it handles. The shutter button feels clicky enough and i havent noticed any lag at all which was my biggest fear. That said, if montana is gonna be super wet, i might actually suggest a different path to stay under budget. You could just grab like three extra Panasonic DMW-BLK22 Rechargeable Lithium-Ion Battery units and a SmallRig S5II L-Bracket 4137 to help with the hand feel. The L-bracket makes the camera way easier to hold for long days without messing with the weather sealing of the main body. Basically gives you the ergonomics you need for way less than the oem grip price. No complaints from my side using that setup on long shoots...

I remember a rainy shoot in the PNW where my off-brand grip just quit on me mid-session... total nightmare. If you cant find the OEM grip, these are decent options for a wedding:

• Use a SmallRig VB99 V Mount Battery for all-day shooting power.
• Protect everything with a Peak Design Shell Camera Cover Medium since sealing is a worry. Quick tip: clean the gold contact pins with a cotton swab to stop any potential shutter lag.