Honestly, most people overspend on V90 cards for the a7iv when they dont really need to. I've shot countless weddings over the years and unless you are doing heavy S&Q or All-I codecs, a high-quality V60 is gonna save you a ton of cash. In my experience, you're better off getting two 128GB V60 cards than one expensive V90 just for the peace of mind of having a backup. Reliability is everything when it's someone's big day. Heres what I recommend to stay under budget:

• SanDisk Extreme PRO SDXC UHS-II V60 128GB is basically the workhorse of the industry and wont break the bank.
• ProGrade Digital SDXC UHS-II V60 Gold 256GB is a killer value if you want more space for long speeches. I've never had these overheat on me during long ceremonies in the summer heat, whereas some of those generic brands get scary hot. Just grab them from a reputable shop so you dont get stuck with a fake... happens more than you'd think.

• Sadly Sony TOUGH-G series SDXC UHS-II V90 cracked on me mid-shoot, total disappointment.
• Use V90 for 10-bit; ProGrade Digital SDXC UHS-II V90 Cobalt is more reliable.
• Kingston Canvas React Plus SDXC UHS-II V90 is better value.

Building on the earlier suggestion, we've basically established that V90 is the safest bet for the a7IV if you're pushing those high bitrates, and that those expensive Sony Tough cards have a bit of a reputation for falling apart. I actually had a scary moment doing a long ceremony last year where my V60 card just couldn't keep up with the data stream during the vows... the camera locked up and I had to pray the file didnt corrupt. Since then, I'm super cautious about anything less than V90 for weddings. You might want to consider these if you're trying to stay under that $150 mark:

• Angelbird AV PRO SD MK2 V90 128GB - these are built like tanks and I havent had one fail yet.
• SanDisk Extreme PRO SDXC UHS-II V90 128GB - maybe a bit basic but they are usually reliable for 10-bit work.
• Lexar Professional 2000x SDXC UHS-II V90 128GB - solid speed, just make sure to buy from a reputable seller to avoid fakes. Honestly, just be careful with heat. If youre shooting 4K 10-bit for 30 minutes straight in a hot room, the card gets surprisingly hot to the touch. I would suggest swapping cards during breaks just to give them a chance to cool down. It might sound overkill, but after that wedding mishap, I dont take any chances with 128gb of footage on the line.

Bump - same question here

Ive ran into this exact issue when I first started pushing 4K 10-bit on my a7IV for some commercial work. I found that the technical overhead for certain codecs is way more demanding than others during long takes. Are you planning to shoot in All-I or Long GOP? Also, do you need to film high frame rate S&Q for those slow-mo b-roll shots?