Maybe this is what you are looking for. This shows statistics on:
physical disks
SDS meta devices
(and my NFS mount points)
Latency is the wsvc_t and asvc_t columns. Read the man page for definition of these columns.
<soneill@chivas:/home/soneill:2267>$ iostat -mxn
extended device statistics
r/sw/skr/skw/s wait actv wsvc_t asvc_t %w %b device
0.10.20.90.1 0.0 0.010.923.201 d1 (/)
1.20.63.10.6 0.0 0.03.020.612 d2 (/var)
0.00.00.00.0 0.0 0.04.826.400 d6
0.10.20.80.1 0.0 0.00.022.201 d10
0.00.20.10.1 0.0 0.00.07.800 d11
1.10.62.70.6 0.0 0.00.020.102 d20
0.10.60.40.6 0.0 0.00.011.400 d21
0.00.00.00.0 0.0 0.00.016.000 d60
0.00.00.00.0 0.0 0.00.021.700 d61
0.20.30.50.3 0.0 0.00.029.901 c0t1d0
1.21.33.51.0 0.0 0.10.022.103 c0t3d0
0.00.00.00.0 0.0 0.00.00.000 c0t6d0
0.00.00.00.0 0.0 0.00.010.800 c1t2d0
0.01.50.23.4 0.0 0.00.34.501 compaq:/misc/solaris-local
0.00.00.00.1 0.0 0.00.24.600 compaq:/home/soneill