I had the same code and same experience going to Daytona for Octoberfest. Only difference is I didn't let off till I got off 95(needless to say it didn't go off till then either). Didn't notice any issues with performance at all, even accelerating harder.
When I got back the next day I checked it out and I lost a bolt on my rear header. The lose header was allowing cold air in the header and throwing the 02 off.
I fixed the bolts (changed all 4 and gaskets) it fixed the code. A few weeks later the code came back. First thought was bolt again but all was good. Changed the 02 and haven't had any issues since.
Check for exhaust leak but it my just be your 02 going bad. The sencond time it started throwing the code it was the same situation at high speeds. Auto zone stocks the bosh 02 and its cheap less than $20. A little bit of a bitch to get to but cheap.