Not sure how this relates to the size of the memory card or how we should purchase a memory card. My Lexar and SanDisk cards bear none of these acronyms and work great.
For the most part, it doesn't. The speed trade-off is minimal, especially if you don't normally shot a lot of RAW bursts back to back, in which case the bottleneck is usually caused by the camera and not the card.
The real advantage, in my opinion, is reliability/longevity especially if you don't replace cards very often. On occasion, I am still shooting some of the 2/4/8GB cards that I purchased with my brand new (at the time) 30D. I only have my 16gb cards now as a result of stepping up to a 7DmkII and getting tired of swapping the 2gb and 4gb cards that I purchased 10+ years ago.