Things these days get faster and faster ( except the lines at Coles and Woolies out near my house...) and the cards we sell for memory are no exception.
Currently in stock I see speeds from 25 MB/second up to 280MB/second - of course there are different capacities in the cards and not all types of card are in all speeds, but there is a fair spread of specification - one would think enough to suit all needs.
I have been advised by one of the company writers for the camera system I use to get the fastest possible card - his reasoning is that it allows me to access all the arcane features of the camera. I expect he is right, but up until now the thing has not been an issue.
Studio shooting is slow. An hour to set a scene is lightning work. Some set-ups are the entire morning and a complete day is not unknown. It was a day that had coffee, pastries, cocktails, and language - but was ultimately successful. In the end the speed of the card was irrelevant. Actually the cocktail was faster.
The computer is the next choke-point for information. Mine is an older iMac and I suspect that it, and the reader in use, restrict the flow to about 35 MB/second anyway. If the card in use is able to discharge at a considerably faster speed, I don't know it. Downloading for he number of images I take is not an onerous process anyway.
You might have considerably different needs. You might shoot at high speed and have to send your data down into your devices and out to the world in split seconds. You might shoot 500 images of one subject before you get it right and are unable to bring yourself to discard 499 of them before you store it away...I've seen people like that on those intervention television shows...They are the ones with rooms full of hard drives and laundry baskets full of single socks...
So don't do as I do; use old, cheap cards and only shoot 50 shots per day...come in and buy some of the super-speed types with far greater capacity. They are good value and reliable. And if you upgrade your computer you will be able to go faster anyway.