I would not personally spend 100 dollars on new racks if I had Blackburn already. Unless you are planing to do any of the weird things CC does on his bike, I think you will do fine on the racks you have. Better racks are out there, but they tend to be expensive, and preferably custom. There are some really cheap racks out there that are just oversized blackburns, at ridiculous prices, and with nice welds. However, Blackburns are just fine. I still have one from around 1990, on one of my bikes.

Folks who tour the world non-stop, often choose custom options because racks do break, and in particular the bolts break, and the frame bits. But those tend to be problems at the 10 000 mile type level, you can do a tour of a lifetime, like a trans-am with Blackburns as multitudes have. Weigh you are carrying has to be reasonable.