However, there has been concern that because the public has heard that the shot is only 72% protective in the US, and the Pfizer and Moderna Covid-19 vaccines are about 95% protective, some will think this is a "second class" vaccine. Experts say those numbers are highly misleading -- and urge people to take whatever shot is first available to them.
Florida's four FEMA-supported vaccination sites -- in Tampa, Orlando, Jacksonville and Miami -- are now allowing people to choose between J&J and Pfizer, according to Jason Mahon, communications director for the Florida Division of Emergency Management.
"Giving them the choice was important," Mahon told CNN.
Those at the Miami-Dade College vaccination site on Wednesday mulled over their options before deciding which shot they wanted administered.
Lolita White told CNN that she is "afraid of needles" and therefore can "only do this once."
"It was liberating," she said about getting the J&J vaccine. "But it was very scary at the same time because ... I'm definitely afraid of needles. The people in there were very supportive. The guy who gave me the shot ... said don't be afraid."
Despite J&J's lower efficacy, White said she was comforted to learn that J&J's research included protection against the new variants of the Covid-19 virus.
Guillermo Muñoz said he trusts that all the vaccines are effective -- but he also preferred getting the J&J vaccine because it required one dose.
"I want to make sure that I'm protected and I want to make sure that, you know, that we protect others," Muñoz told CNN. "The quicker we reach herd immunity, the quicker we will be able to go back to as normal a life as we possibly can."
Others said they prefer Pfizer -- citing various reasons, including that it's been available longer.
"I just don't know much about it (J&J vaccine), so I would rather go with something that's well known," Rocio Mendez told CNN.
Ruth Watkins also opted for Pfizer -- she said she believes in the company so much that she decided to invest in it.
"I don't choose to buy Johnson & Johnson products and haven't for a really long time," Watkins told CNN. "And Pfizer was just a good choice."
Anthony Fauci, the nation's top infectious disease expert, urged Americans to take any of the three "highly efficacious" coronavirus vaccines now available to them and not delay getting one vaccine over another.
"We want to get as many people vaccinated as quickly and expeditiously as possible."
Patricia Gibbs, who got the Pfizer booster shot on Wednesday, echoed Fauci's opinion.
"We all need to get this shot to protect everybody," Gibbs said.