Ok! Well I knew the 4th gen has been used in the UK and other countries for a while. Thanks for the info. I will pass it along to others who ask.
The DUO can be ordered by your physician in the United States. So far today, it's still difficult to find walk in clinics or HIV clinics offering the 4th Generation test as it was only just this June that 4th generation was made the "go-to" test by the CDC to cut detection times from acute infection down 2 weeks. Slowly but surely over the course of the nest year or even months will you your clinics begin to incorporate 4th generstion test.
Don't forget funding plays a major part in that process. Those clinics pay for those test by the government if they offer free hiv blood testing. If they're not heavily funded, don't expect 4th generation test soon. The 3rd generation test works just as good 6 weeks onwards when the P24 antigen began to fall due to antibody production.
I have run into the same problem!