They all appear to be different versions of the same product. Don't worry about the surge suppression - power surges (in the US, at any rate) are rare and modern electronic power supplies compensate automatically for them.

Spike current is the maximum current (measured in amperes, A) that the device can handle. Though I think a more useful measurement of power surges should be in Joules. Regardless, don't worry about it. Just buy it for the outlets and the USB ports.