It is my understanding that the 5857 and the TE-44 are very similar. TE-44 is less expensive though.
The only real difference, as I understand it, is the new compressor is the same size but CNC'd instead of cast with the fancy new angles etc and more efficient. The exhaust side is where gains are to be had though. The TE44 uses an old style T31 exhaust wheel where the 5857 has a much more efficient exhaust side. You'll only ever know though when you approach 120mph in the quarter and then you may get an extra 2mph out of the 5857/5858 over a TE44. Both should be great on the street and you'll need over 25psi on a stock headed car to see the difference, maybe even 30psi.