Honestly, for a 12-hour wedding gig in Seattle where it might rain, I would be really careful with the cheap stuff. I tried a Neewer NW-5D Mark IV Battery Grip a while back and the joystick felt like a toy. It was super frustrating during fast sequences because it would lag or just miss clicks entirely. When youre shooting a ceremony, you really cant be fighting your gear. If you go third party, make sure to consider these risks:

• Weather sealing is basically non-existent on the budget brands. If it rains in Seattle, water gets into that battery tray and your whole camera might short out.
• The buttons often dont have that tactile click. They feel mushy which makes it hard to know if you actually hit the shutter half-way for focus.
• Plastic quality. Most of them dont use the same magnesium alloy, so they flex a bit when you have a heavy lens like that Canon EF 24-70mm f/2.8L II USM attached. I would suggest just biting the bullet and getting the Canon BG-E20 Battery Grip. It matches the body texture perfectly and the weather sealing is legit. If you really cant swing the price, the Vello BG-C14 Battery Grip is slightly better than the Neewer one in my experience, but it still isnt perfect. Given its a wedding and your reputation is on the line, dont risk it for a hundred bucks... that peace of mind is worth way more than the savings.

Building on the earlier suggestion, I totally get the wallet pain after buying glass, but the Canon BG-E20 Battery Grip is honestly a different world compared to the cheap ones. That grip has been on my camera for about two years now and I'm super satisfied with how it handles. When you're shooting a marathon 12-hour day, you really dont want to be second-guessing if your shutter is gonna fire or if the joystick is gonna lag. Cheap alternatives usually feel like hollow plastic toys. Here is why I stick with the official one:

• magnesium alloy build matches the 5D IV weight perfectly so it doesnt feel front-heavy
• weather sealing is legit, I've shot in some nasty drizzle and never had a communication error
• the shutter button has that distinct two-stage feel instead of just being one big mushy press Ngl it sucks to spend more money right now, but for a wedding pro, it's basically insurance. It makes the vertical shots so much more comfortable for your wrist too... my carpal tunnel basically disappeared once I started using one. Just make sure you're using official Canon LP-E6N Lithium-Ion Batteries too, since third party ones sometimes give weird battery readouts on the grip.

Been thinking about your dilemma and honestly, I've been down this road many times. In my experience, the real issue isnt just the plastic feeling, it is the electronic communication. I used to try to save money on accessories until a third-party grip I was using on an older body started draining my Canon LP-E6N Lithium-Ion Battery while the camera was turned off... super annoying when you wake up for a shoot and youre already low on power. I once compared the Canon BG-E20 Battery Grip side-by-side with the Vello BG-C14 Battery Grip for Canon 5D Mark IV. The Vello is probably the best of the third-party ones, but the buttons just didnt have that distinct click the 5D body has. When you are shooting in the rain in Seattle, you need to feel that tactile feedback through your fingers without looking. Plus, the weather sealing on the official one uses the same gaskets as the camera. Tbh, if you are shooting a high-stakes 12-hour wedding, the risk of a cheap grip shorting out your main body is just too high. I always stick with the brand name for electronics now. Its just safer... One more thing to watch out for is that the third-party pins often dont align perfectly, which can cause the camera to randomly restart if you bump the grip. Its not worth the stress on a wedding day.

Can confirm this works. Did the same thing on mine and its been solid ever since.

Good to know!

Re: Good to know!

• Just caught this thread and wanted to jump in because I have a bit of a different perspective on the whole brand-new-vs-cheap-knockoff debate. I have been using the official version for years now and honestly I am so satisfied with the reliability that I would never go back. Not sure but I think you might be better off looking for a used original one instead of a new third-party one for that Seattle gig.
• I am pretty sure I found mine for like a hundred bucks on a forum classifieds section and it has been solid ever since.
• Someone told me once that those off-brand ones can actually mess with the camera electronics if they short out in the rain, which basically sounds like a nightmare for a wedding pro.
• If you are really in a rush, just rent the official one for the weekend. It is cheap and you get the peace of mind without the huge upfront cost right after buying that lens. I am always a bit cautious with gear that has power running through it, but I have been really happy going the used OEM route. It just works well and you dont have to stress about the joystick failing when the couple is walking down the aisle.

Ngl I saw this and had to jump in because weddings are just brutal on the body! I totally get the wallet pain after that lens purchase but honestly for a big 12-hour gig in Seattle you gotta be so careful!! I think I remember hearing that the weather sealing on those cheaper third-party grips is basically non-existent compared to the magnesium alloy stuff. If it starts pouring and water gets into that battery tray because the seal isnt tight... that could be a total disaster for your camera body! IIRC the official ones have actual rubber gaskets around the communication pins and the door to keep things dry. I'm not 100% sure if any budget brands actually match that level of build quality but I'd be way too scared to risk a pro body on a rainy day with a thin plastic tray. The joystick response is everything too! If it lags even a tiny bit you're gonna miss the kiss!