Transferring Data From AS400 To SQL Server

Hi all,
I am working at insurance company that using AS400 as it main server. All transaction data is already kept for about 10 years (or even more..). This data is growing larger from time to time, and after several upgrades (that cost a lot!), my supervisor has an idea to partly move the data from AS400 to SQL Server. (since the cost for upgrading sql server is cheaper than AS400).

So.. let say, we only want to kept data in AS400 from 4 years before until now (2004 – 2007), and the rest of data is kept in SQL Server.

So first, all transaction data from 1997 – 2003 is transferred to SQL and deleted in AS400.
If user queried data and didn’t found the data in AS400, it will search the SQL, if data is found in SQL, then data is transferred back to AS400 and deleted in SQL.

I’m using SQL Server 2000 DTS (use HiT OLEDB) to transfer the data from AS400 to SQL and vice versa.

I wanna ask if anyone has done this before? What’s the difficulties by using this approach? (btw, I will implement the DTS using user control in vb.net)

Or anyone has a better solution to overcome this problem?

Thanks,
[RU]