The first is a clincher while the second is a tubeless. Why should a tubeless tire cost more than a clincher?

Not only do they cost more but you can almost buy a pair of the GP4000's that so many people use for the price of a single GP5000S. It's probably more than $100 for a GP5000TL in a shop in case you run over a killer piece of glass in front of a bike shop.

While Continental is the most popular racing tires (Vittoria is actually a better racing tire IMO) the reason I would change is because the MAXXI tubeless tires I'm presently running feel dead. They actually look narrower than a 25 mm Continental but I just went out into the garage and measured them and they are identical. So I guess the Continental is deeper.

They now have Goodyear tubeless tires and perhaps I try those for the Basso.. They are a little cheaper and my experience with Goodyear car tires is pretty good even though I'm pretty negative about a lot of things.

In any case, the Continentals are WAY too expensive and while the top of the line Vittoria I have are tubeless I will use them as clinchers on my Colnago.

I guess I will wear the Maxxi's out but only on economic principles.