tbh Godox V860III-C Speedlight for Canon worked better for me than Canon Speedlite 430EX III-RT:
• Li-ion battery lasts WAY longer
• Recycle speed is faster for weddings
It's cheaper too!! gl

sooo I used to use heavy OEM flashes until one literally fried mid-shoot. so disappointing... Anyway, check out the Godox V350C Li-ion Flash for Canon. It's like $160 and way more compact for events. The Li-ion battery is a lifesaver for recycle speeds. TL;DR: Get the V350C. It's budget-friendly, small, and the HSS works great on ur 6DII.

Late to the party but in my years of shooting, I would suggest these for the 6DII: * Yongnuo YN685 II Wireless Flash for Canon: Pro: Amazing HSS. Con: AA batteries.
* Godox TT685II-C Flash for Canon: Pro: Great UI. Con: Bulkier.
* Neewer NW655-C TTL Flash for Canon: Pro: Dirt cheap. Con: Slower recycle. Yongnuo is my pick for budget consistency—its literally never let me down at a wedding... gl!

Re: "> I’m also curious if third-party options like..."

• I actually have to politely disagree with the idea that you need a high-end TTL system to get good results. When I first started doing event work with my 6DII, I was obsessed with finding the perfect automated flash, but I found myself constantly fighting the exposure compensation anyway. I ended up switching to a completely manual approach with a basic setup I pieced together myself. It took some practice to get the hang of adjusting power on the fly, but honestly, I am so much more satisfied with the consistency now. Using simple gear and even some DIY modifiers made from cardstock has worked well for me because there is no communication lag or weird TTL misfires. Basically, the one I got was just a fraction of the cost of the name brands, and it forced me to actually understand lighting. No complaints here, it was a solid way to learn... kinda wish I had started that way tbh.

Just wanted to say thanks for everyone chiming in. Super helpful discussion.

> I’m also curious if third-party options like Godox or Yongnuo are reliable for high-speed sync on this specific body. Ok so, one thing to really watch out for with the third-party vs OEM market is the firmware stability. Tbh, while the budget brands have basically caught up in terms of raw specs, they can sometimes have weird communication glitches with the 6DII’s E-TTL II system during high-pressure shoots. I've noticed in some technical reviews that the build quality on the hot shoe feet varies a ton between brands. Some of the cheaper ones use plastic mounts that can snap or, well actually, the pins don't align perfectly with the Canon contact points, which causes the HSS to drop out randomly. If you’re doing weddings, definitely check if the brand you pick has a reliable way to update firmware via USB. Wait, no—some of them require a specific proprietary dock that costs extra, which is realy annoying. Just a heads up that "compatible" doesn't always mean 100% reliable across every single shooting mode. I’d be more worried about the physical connection stability than the recycle speed tbh.

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