No one seems interested in answering so I will give it a quick shot.

At this young age I don't think it will matter.  I do believe that a young
cat will be the better if you have two cats around.  It gives them someone
to play with when you are not around.  This will lead to a 'bit less'
destruction to play.  The kittens have someone their own age to rough house
with.  Plus there is the benefit for you of watching WWIII on the floor as
the two terrors have it out.

The last time I had young felines to watch was 20 years ago, I keep being
adopted by full grown cats these days, but I do grow with females having
kittens after kittens, common in those days.  The kittens don't care about
the age difference at that age.  They just have fun playing.

Go for it, I don't think you will regret it, in fact I am envious.

Mike