Lexar Dual Slot Card Reader; 2.0 vs 3.0?

Hello,

Looking to purchase a CF/SD card reader for my 5D2/1D3. I'm interested in the difference between these two models. I can get the older version for $10...less than one-third the cost of the later version.

Thanks!

Do you have a computer with USB 3.0 ports? If not, how close are you to replacing your current computer? If the answers are "No" and "Not very", then USB 2.0 will be fine; if "Yes", or "In the next few months", go for the USB 3.0 readers - USB 3 is much faster than USB 2, but both the computer and device need to support it.

A USB 3.0 device will work in a USB 2.0 port, but only at USB 2.0 speeds, so if you have no plans to move to USB 3.0 very soon, count on falling prices for the peripherals by the time you're ready to step up.

Thanks! I use an old laptop, so looks like 2.0 is the way to go.

USB2.0 has channel bandwith of 480 Mbit/s or 60MB/s. That is channel bandwidth only. For storage protocol, BOT, after encoding, commands, overheads, the actual user data rate of the channel is about 40MB/s. Most USB drive and read can only operate at about 20-25MB/s.

USB3.0 has channcel bandwidth of 5Gbit/s or 640MB/s. Again, with all the overhead, actaul archieveable user data rate is about 450MB/s, which is very fast. Obviously, you need both USB3 on the reader side and the PC side. Also, Window8 is a lot more efficient with USB3 than previous windows. To go into a bit more detail, Win8 transfer chunk for USB3 can be up to 512KByte, earlier Windows are up to 64Kbyte. The bigger the chunk, the more efficient.

If you PC has USB3, there is no reason not to get a USB3 card reader. If your PC does NOT have a USB3 port, then there is no difference because a USB3 card reader is backward compatible and will operate at USB2 standard on the USB2 port.