Very different systems, but work in the same way.
The Telair system is more modern, though unfortunately not mature yet.
All the large PDUs in the constant section have been replaced by little (3") ones which are fixed into the lock rails. The disadvantage of this is that you can no longer move locks around for non standard loads. Similarly, these things no longer have a clutch; if the thing fails, you have to replace the unit (...and they fail often). Freewheeling the pdu is no longer an option.
All the castors common on the TRW designed (standard Boeing) system have been replaced with Ball Transfer Units (BTUs). We've had a lot of trouble with these. They simply break.
All locks & guide rails, door sills have been replaced - they function in the same way, just made out of lighter materials.
PDUs 1-5L/R and 17/18/19L/R are of a new design. No longer pneumatic but solid with a rubber covering (which wears off very quickly). They do turn faster though.
The whole system was supposed to be lighter than the original system; due to various modifications (eg strengthening the BTUs), system weight has increased.
Given the choice, I'd go back to the original system. This is unfortunately no longer offered by Boeing.
Some other points - the 3 inch pdus have electronic eyes; they only drive when the pallet covers these eyes - takes a little getting used to; you initially think the system is malfunctioning. There is also a neat little computer system at the sidewall at position RL. This thing can test each and every pdu, giving you a status message (eg operative/inop, overheated....)
Hope enough for now.