[zeeboo]

Note these tests were run on Python 2.2 which makes the results old enough to almost certainly be invalid. Last time I checked, straight string concatenation was faster than everything else for the types of inputs I was dealing with.

[pdonis]

straight string concatenation was faster than everything else

As I understand it, this is implementation dependent. CPython has gone to some lengths to optimize its string concatenation code to do things behind the scenes that are basically equivalent to some of the faster methods given in the article. Other Python implementations have not necessarily done that, so string concatenation can be a lot slower.