The good thing about the new pair is that they haven't made any dramatic changes. This is good as the design on the old pair was pretty sound.
The reflective parts have been added to slightly and really do shine when light hits them.
Another addition is that the length of the over trousers can be adjusted quite easily to suit different leg lengths.
The important bit is how waterproof they are. The old pair lasted ages and being an all weather Brompton cyclist, they laboured under some terrible conditions, performing well. Today I went on my daily commute early this morning and would have been soaked without these over trousers.
I doubt if they are breathable but I didn't feel hot or sweaty as a result of wearing them. They are comfortable and a good fit - even when wearing suit trousers underneath as I always do.
There are many other makes and price ranges however in my opinion these are one of the best. If you're a winter commuter or worried about getting wet, these just might be what you're looking for. I managed to get these for £48 online which is a pretty good price.