I like having two piece rods for the convenience.  It is so much easier to keep in my car for those spontaneous trips.  The next vacation my family goes on will include fishing for me, and there is no way I can get a 1 piece rod in the car with the kids and all the luggage. 

Yes, I have cast off the top half a few times, but not very often.

Does a two piece rod effect the performance of the rod at all?

I would feel better and more comfortable fishing with a one piece rod because I will be rested assured that it won't unsnap or come apart. I will have direct contact throughout the entire blank hence even more sensitivity.

The two piece is more expensive and when you see the two piece rod compared to the one piece rod, the first guide on the two piece is MUCH closer to the second guide and further up. That causes line flutter off the reel and that is one cause of wind knots

I think you've answered your own question. You probably will not be satisfied with the 2-piece rod. There's no sense wondering if you should have traded.. The Avid is a fine rod. Enjoy it and share your thoughts about it  :) :)