I was pleasantly surprised when I saw that Radio Shack is now selling Makeblock robot kits. I have mentioned before on this site that the Makeblock kits are pretty awesome, so I am naturally happy about this.
Although the kits are a bit pricey, they are very well made and will hold up a long time. Not to mention that it is about the sturdiest and torque'iest robot frame that you can drive around with an L298n motor driver shield for your Arduino. The little geared motors that come with the Makeblock kits are quiet and have tons of torque for their size. They will get an L298n chip warm after several minutes of hard driving, but I have yet to overheat one.
Go Radio Shack!