My experience with an Antec 1030 is that it is only as loud as the components installed. The design is so open that it has almost nil sound-deadening. With two L1A panaflos, it should be very quiet. I'd try mounting them both blowing out the back. Panaflos are sleeve bearing fans, BTW
Depending on your total system, you might need/want more airflow-add two more on the front blowing in.
Of course, you could spoil the whole thing with a 38cfm-46dba 60mm screamer on the cpu heatsink. Whatever fan is the noisiest is the one you'll really hear, the others sort of settle into the background behind it, lifting it to a higher level.
Not stated in very scientific terms, but that's the way my ears perceive it.