I use the 60mb/sec cards with no problems. The fast cards might make a difference if you are trying to shoot high fps sequences and need a extra frame or two before the buffer fills. You can also cut the transfer time to your computer if you have a good USB-3 reader.
Get what you need, 60 mb/sec works fine.
One thing to consider, is that if you use dual cards and write to both, your speed will be limited by the slowest card, so even 60mb/sec will be overkill if a class 10 SDXC card is installed.
Lexar 1000x gives you MUCH more than just a frame or two extra compared to the Sandisk 60MB/s cards, heck it gives much more than that even compared to the 90MB/s cards.
Of course it depends what you shoot. If you do tripod based landscapes it's a total waste of money (other than mayeb saving a little time uploading to the PC later). If you are doing anything that can need lots of bursts at times man the lexar 1000x can be well worth it, yes, noticeably longer burst even compared to ExtremePro 90MB/s and insanely different compared to say older Extreme III cards.
The $120-$150 deals on the 32GB lexar 1000x make the price OK.
But it depends, for some it's more than worth it, for some a total waste and a 32GB card on some $15 deal will be fine.