I prefer SanDisk Extreme Pro 128GB CompactFlash 160MB/s for reliability over Lexar. For grips, the Canon BG-E20 Battery Grip is sturdier, while the Vello BG-C14 Battery Grip is cheaper but feels plasticky.

Yo, congrats on the 5D IV. It is an absolute workhorse even years after launch. Since you mentioned weddings, you definitely want to utilize that dual card slot for redundancy. I usually run a CF card in one and an SD in the other for instant backup just in case a card fails. You dont really need the most expensive SD card out there for backup, something like the Kingston Canvas Go Plus 128GB SDXC UHS-I V30 works perfectly fine for stills and saves you a chunk of change compared to the high-end pro brands. For lighting, honestly, dont bother with the official Canon Speedlites unless you just have money to burn. I swear by the Godox V860III-C TTL Flash for Canon. It has a built-in lithium-ion battery so it recycles way faster than standard AA ones, and it is basically a third of the price of the Canon equivalent. Its been a total lifesaver during long receptions where I cant be fumbling with loose batteries. Also, grab a Neewer Dual USB Battery Charger for LP-E6N. It lets you charge two batteries at once via a USB power bank or a car adapter, which is great if youre on the move. Finally, just pick up a basic Altura Photo Professional Cleaning Kit to keep that sensor and glass clean. Spending a ton on flashy gear is fun, but these practical, budget-friendly bits are what actually keep you shooting without the stress. Enjoy the full-frame life!

Good to know!

Late to the party but screen protection is a huge deal in the field. I wasted money on cheap plastic films before switching to Expert Shield Glass Screen Protector for Canon 5D Mark IV. It basically feels like actual glass and doesn't lag the touch response. Also, the Wasabi Power Battery LP-E6N 2-Pack has saved me on long wedding days when I didnt want to drop hundreds on Canon originals.

Bookmarked, thanks!