people who have a good energy
Is not the same as
people who have a good energy about them
I am not even sure how one would interpret people who have a good energy (I guess the interpretation depends on one's religious or metaphysical outlook on life), but people with a good energy about them, meaning "around them", clearly seems to indicate that they radiate something positive, they make the people around them feel good.
As such, the two options are as different as, say
I like people that have a blue coat (even when they left it at home).
I like people who have a blue coat on. (They are wearing it.)
I agree it would be probably strange to judge people on whether they wear that coat when I meet them, but I hope you understand my point :)