I recently ordered a new batch of the pads from Amazon and used them this morning.
They are much better than the ones that came with my stim.
These are the ones I got-
http://www.amazon.com/gp/product/B00..._ya_oh_product

The connectors are generic it seems - so you can choose the shape/price /brand that you like.
I got the square ones this time, had the rectangle before and i felt like I was always getting them crooked. They still work fine crooked or not but I liked them to be even.
{just my personal "thing " LOL }

I'm always fixing crooked pictures on the walls and stuff.