Looking at them in the catalog, they seem to be variations on their "original" line-up, but with Toulouse-like leather.
I suppose it's probably an improvement over the crap leather now on the original line-up, but I personally have never liked the whole "covered leather" trend, and on the Toulouses in particular, I don't think it wears well. I can't imagine they would have used leather that is a better quality than Toulouse, so I would assume the same for the Circuit Premier line as I know for the Toulouse - that it looks nice initially, but won't wear well.
Now, all that said, I always thought the older Circuit saddles were very decent saddles for the price. The newer (current) ones have crap-tastic leather, though, so I stopped recommending them, primarily for asthetic reasons. Even though I don't think it will wear well, I think that I could potentially again recommend Circuits (the Premier line), because the asthetics are now more in line with the price and mechanics of the saddle.
I still wouldn't purchase it myself... but I would be more likely to recommend to the budget-concious or entry-level rider (still behind a higher-end used, though).
Patterson and Ebert give it 3 1/2 stars (out of 5) and one thumb up.
Founder, Higher Standards Leather Care Addicts Anonymous
Capitalization is the difference between helping your Uncle Jack off a horse and helping your uncle jack off a horse.