for a dedicated looper, rc 2 is prolly one of the cheapest looper pedal around with the kind of features it has.
There are also delay pedals out there with looping function, but the features and looping time is way less then rc-2.
If really wanna a good looping pedal to start with, the rc is actually quite a good choice.
If just wanna a simple looper, then get those delay pedals which has looping function. But the prices still wont be cheaper and can be either the same as rc 2 or much more.
For the differences, perhaps you can list the info which you dont understand and see if we can help. Hehe, you be prolly more confused and totally overwhelmed by what we say if we dont know whats the thing you are not familiar with.