Hi,
I tested RB532 with MT 2.4.46 as a ipsec client end-point router connected to Linux router with Openswan.
With md5/3des/modp1024 I had about 5,8Mbit/s and 100% CPU on RB532 (2.4.46).
With md5/3des/modp1024 I had about 1,2-1,6Mbit/s and 100% CPU on RB532 (3.0rc5).
So, something is wrong in 3.0rc5.
bye,
Peter