(adsbygoogle = window.adsbygoogle || []).push({}); So I'm going to be using an E3 flasher. I have a slim and haven't checked to see what exactly the slim is, but I've seen some solderless E3 flashers and I'm curious if they work. Which ones do I buy?

You don't need to solder, this for example would work You must login or register to view this content.

Please check this thread on ps3hax.net: You must login or register to view this content.
There you will find all the information you need to downgrade your ps3. BTW all e3 flasher have both options,
you can go without solder which is the clip option (Its a lot harder to downgrade and it has a bigger risk of bricking
your ps3, due to the fact that you could make a bad dump) or you can go with the e3 linker which solder.