Here is how the chances have changed from the 1st week to now, assuming you can afford to enter with the maximum number of entries possible and did so:
Air Vent Car Mount: 6.97%
PowerCore 5000: 3.797%
PowerCore+ 10050: 2%
Bolder LC40 LED Flashlight: 16.85%
SoundBuds Lite Bluetooth Headphones: 13%
PowerDrive 2 Elite with Micro USB: 81%
I think the steady increase in chances from week to week is coming to an end. The probabilities will likely stick around what they are now.
Now that we know you can't win two of the same products in one week, perhaps it is wise to bid only one entry, though then, you probably won't win anything.