H1B Transfer Scenario [No H1B VISA Stamp]

Hello, I have a tricky situation with respect to my H1B petition.

Company A has filed a H1B petition for me which is valid till 2015. But company A hasn’t sent me for VISA stamp. Hence i dont have H1B Visa. I just have an approved H1B petition.

Now Company B contacted me and said they will file a transfer/new petition for me and will send me for VISA. I have few questions here.

  1. If company B files a new H1B petition for me, then what happens to the status of the petition filed by Company A?

  2. If I go for VISA stamping using Company B’s petition and for some reason the consulate issues a 221(g) query, then in the mean time can i go for VISA stamping again using Company A’s petition (assuming that Company A also wants me to get the VISA)? Will I face any issues?

Situtation is, Company A wants me to go for VISA stamping but not urgently. It could happen over a months time because of internal approvals. But Company B have an urgent opening and hence they want to do the transfer using PP. So i am in a kind of confusion on which way to proceed. If i go with Company B’s petition, and while its under process, what happens if Company A also wants me to go for VISA stamping.

Please Advice.