I'm thinking I need some new tires, they are sporting some large cracks/holes, and they seem to be wearing from the inside such that the fabric can be seen and is poking out. I have a flat nearly every time I ride, which is frustrating to say the least. These only have 1500 miles on them.

I currently have 700c x 25's. Can someone explain the difference in feel of riding on 23's instead of 25's? I like my 25's, I'm just curious about 23's.

What is your favorite kind of tire (brand/model)?

I don't race, just general rides and commuting. I'm averaging around 80 mi./week right now, hoping to bump that up to 100 - 150 as the weather continues to improve. I ride mostly asphalt and chip seal roads (with some leftover gravel from the winter) in dry conditions. Oh, and I like to descend, fast, on curvy roads, don't know how that factors into the 23's vs 25's equation.

Thanks!