I also tried the off the shelf radiator patches while waiting for a new radiator. After reading this forum, I had a good feeling it would fail (crack was front-top of radiator). To keep the car decently clean if and when it failed, I duct taped a folded up towel over the patch to absorb the radiator fluid that would leak out when it failed. It did fail after a few days (could tell because the towel was wet). The towel also seemed to help keep the embarrassing steam from coming out from under the hood while stopped in traffic (I drive though a pretty nice area to get to/from work and it is embarrassing to have a steamy car next to BMWs, Mercedes, etc.).

Note I drive the car only 10-12 miles at a time to/from work taking about 20 minutes.