ugh i am in the exact same spot right now trying to find cards for my new fx3 rig. its such a headache comparing sustained write speeds vs burst speeds when manufacturers hide the real data in the fine print. i have like ten tabs open right now just looking at vpg ratings... tips for when you are looking:

• always look for the vpg400 logo specifically if youre doing 4k120 all-i
• check the thermal data, some cards like ProGrade Digital CFexpress Type A Gold 160GB handle heat better than the cheaper generic ones honestly i am torn between that and the Exascend Essential CFexpress Type A 180GB because the specs are so similar but the price delta is annoying. glad i found this thread tho lol.

Lexar Gold Series CFexpress Type A Card, Offers up to 900 MB/s read and 800 MB/s write speeds.

No way, I literally just dealt with this yesterday. Small world.

I absolutely love the FX3, its such an amazing camera! Since youre pushing into 4K 120fps territory, reliability is everything for a professional workflow. Ive been running the Delkin Devices Black CFexpress Type A 160GB for a while now and they are fantastic!! Here is why I prioritize these specifically for safety:

• These handle heat much better than standard cards during heavy 10-bit 4:2:2 sessions.
• VPG400 rating ensures you wont drop frames when shooting the big All-I files.
• Every card is individually tested before shipping which is an amazing peace of mind factor!
• They offer a 48-hour replacement policy if a card ever fails on you. Seriously, dont risk your footage on cheaper SD cards for high-speed work. Sticking to a ruggedized CFexpress Type A is the only way to go if you want zero failures!

For the FX3, you'll want CFexpress Type A cards for the best performance, especially if you're shooting 4K120p or All-I codecs. The Sony CEA-G series cards are reliable but pricey - the 80GB or 160GB models work great. For a budget option, the Angelbird AV PRO CFexpress cards offer solid performance at a lower cost. Make sure whatever you get is rated for at least 700MB/s write speed to handle the FX3's highest bitrates without dropping frames.

I totally agree that you need those high speeds, its basically essential if your doing 4k120. I’m pretty new to the FX3 and I actually had a reallyyy scary experience last month with a card I thought would be fine. I thought I was being smart saving money but it ended up being a disaster tbh. - The card got way too hot during a long shoot.
- My camera actually threw an error and just stopped recording.
- I lost some of the footage and the stress was sooo not worth it. So basically now I’m only looking for stuff that’s super reliable because your always gonna regret it if the card fails. Does anyone know if heat is a bigger issue with certain types? I just want something that wont fail me again tho.

Honestly if youre worried about reliability, stick to the V90s for most stuff unless you really need that 120fps. Those CFexpress cards are just so pricey, it makes me rethink my whole gear budget every time I look at my cart. I actually spent like four hours yesterday just trying to reorganize my studio closet because the new hard cases I got are just slightly too big for the shelving unit I bought last month. Its so annoying how one small measurement being off ruins the whole flow of the room. I ended up just moving the entire desk to the other wall and now the lighting is all weird because of the window. My wife thinks I am crazy for spending my Sunday moving furniture instead of actually editing lol. Anyway sorry kinda went off topic there, but yeah, just make sure you check the warranty on whatever you buy.