I've just bought two 128GB cards, a Transcend one and a Toshiba one, both UHS3. I've used 64GB Transcend cards for the past 2 years and find them very reliable. I tried both in my X70 at 4k 100Mbs and they seem to work fine. The Toshiba card was much cheaper than the Transcend card ( approx $48 and $77, I live in Thailand where prices are different from the US!)
My question is- does anyone have experience with the Toshiba cards, Are they reliable? I don't want to start depending on them only to find they fail at some critical time.

At some point, nearly every card will fail. I doubt there are any that offer 100% guarantees of data integrity. It's happened to me, and to nearly every shooter I've worked with. That being said, stick with name brands, and if you find a brand that has worked well for you in the past, keep with it.

I've always used Sandisk, and have had a micro SD card become unrecognized by a GoPro, so that's one card out of 30 that failed on me.

For this reason I have maxed out at 128 gb, the potential data loss from using larger cards would be unacceptable.

The other obvious issue is fake cards which are everywhere and usually fail from the get go or soon afterwards.

Paul :-)

I changed to digital from film when it first started in our industry and have used many different brands and suppliers over the years. The ONLY brand and supplier I can rely on is Sandisk and B&H.

No failures, no counterfeits!

thanks, I think Transcend are very reliable as I pointed out but has anyone experience of Toshiba cards?