EB3 VISA processes USA

Hi!

I’m from Sweden and I have a few questions about immigration and EB3 Visas.

I’m a Swedish educated Registered Nurse, BSN. I’ve been working as a RN for the past 2,5 years in Sweden. I’m licensed to practice as a RN in the state of NY, and I hold a Temporary License in Pennsylvania (currently waiting for my permanent license to be issued). I’ve passed the NCLEX (obviously, since I have my US RN licenses), I’ve got my VISA-screen certificate (which also means I passed the IELTS-test). So basically from my knowledge, I have everything that is needed for an EB3.

I have an employer in the state of Pennsylvania that wants to hire me. They referred me to a law firm 1 that told me if I pay for premium processing I'll be over in the US within 3-6 months. If not 12 months +. This law firm says I'll get my GC after a few months being in America. However I wanted to double-check this so I asked another law firm (2) about the process.. and that law firm (2) tells me that its impossible to get an EB3 visa within 3-6 months and then have a GC in your hand a few months after you move. That you need a H1B visa move to the US, work and during the time you work - approx 2 years then you get a GC.

So I have two law firms stating different things.. and now I don't know what to do? I've got a contract that I can sign and they will file my petition etc.. however.. I wanna make sure I get the EB3 visa not the H1B.. haha I'm so confused...