[Exim] caching question 4.20

If I do multiple lookups (say an RBL for instance) and set a $acl_c0 = yes

Is this quicker to test $acl_c0 = yes later or do the RBL lookup again.

What I'm trying to do is test 8 RBLs for statisical tracking.  I was going
to do something like:
warn    dnslists = somerbl
    set acl_c0 = $acl_c0 somerbl=yes
warn    dnslists = anotherrbl
    set acl_c0 = $acl_c0 anotherrbl=yes

then later:
deny    condition = ${extract{somerbl}{$acl_c0}{yes}{no}}