I went to a Hot Wheels collectors' event at Kmart on Saturday. There, you had to get a ticket and there was a raffle where they randomly draw out your ticket number. Each person got to open a new case of Hot Wheels cars and choose five of them while the rest were going to be put on the pegs. Why do we go to these things? Because of the Treasure Hunts and "Super" cars. Those are extremely difficult to find in the "wild", because employees and vulturous collectors usually get to them before anyone else. But when you go to these events and go through the boxes, chances are, you will find a Treasure Hunt or "Super" car among the other cars. And trust me, these things are valuable.
A Treasure Hunt or a "Super" car may retail for the standard retail price of $1.07-$1.50 when found, but due to their rarity and demand, they will easily sell on eBay for 50+ dollars!
With all of that said, several people got a "Super" '71 Dodge Challenger, a few got a Treasure Hunts Tyrell P34. I got a "Super" '71 Dodge Challenger, along with a regular one. The difference between a regular and "Super" Dodge Challenger is that the regular has plastic tires while the super has redline rubber tires. Also, the super has a stripe on the hood while the regular doesn't. The paint on the super is Spectraflame, while the paint on the regular is just a regular sheer paint.
Here's an example of how valuable these things really are. This isn't mine.
http://www.ebay.com/itm/71-Dodge-Challenger-SUPER-Treasure-Hunt-2012-Hot-Wheels-/190632950995As a Hot Wheels collector, the only cars I keep in the pack are rare, valuable ones. Anything that's common I open and play with.