Dom, Paul and Joe many thanks for the replies and good suggestions.

I've decided to go with 2 x T2000's each with 8 Cores and 16GB RAM with 4 x 
73GB 10k SAS's.

Joe, right on the money with regard to the SL500. My suppliers matched the 
quote I got for the Scalar i500 so will just add a couple more drives and 
probably a Library expansion.

For DSSU I've opted for a StorageTek 6140 array maxed out with 500GB SATA-II's. 
Looked at the price for 300GB 10k SAS's and the cost was simply not worth it.

It's a shame that NB6.5 / Solaris x64 is not here as the X4500 would be a 
cracking box and I could probably do away with the external array. List price 
was around £17k during the Sun Anniversary sale!

Many thanks once again,

Dale