DB2/400 <--> Oracle questions

Ok,

It appears that Oracle provides 3 (ok 4) products related to 
DB2/400 <--> Oracle access:

1) Oracle Transparent Gateway for DB2/400
        --runs on iSeries
       --Handles Oracle --> DB2/400 access
       --TCP/IP
2) Oracle Transparent Gateway for DRDA
        --runs on a host system (Windows, UNIX, Linux, ect)
        --handles Oracle --> DB2/400 access (or any other DRDA server)
        --uses SNA or TCP/IP 
3) Oracle Access Manager for AS/400
        --runs on iSeries
        --Handles DB2/400 --> Oracle access
        --uses TCP/IP

4) Oracle Generic Connectivity
        --runs on Oracle System
        --Handles Oracle --> DB2/400 access
        --uses ODBC or OLEDB driver to access DB2/400

IBM Provides one product:

1) DB2 Information Integrator (formally DataJoiner)
        --runs on a (non-iSeries) host system
        --Handles DB2/400 --> Oracle access
        --uses TCP/IP


Now it appears Oracle packages options 1-3 together at a cost of $35,000.  
Option 4 is built into the Oracle DB software already.

IBM's product is $25,000 to $50,000 depending on rather I need the Advanced 
edition or could use the Standard edition.


Given that the Oracle solution provides bidirectional capabilities, it would 
appear to be the solution of choice.

However, does anyone have any experience/comments about the above products?

In particular:
--Is there any reason to choose the Oracle DRDA TG over the DB2/400 TG given 
that we have only the iSeries to connect to and plenty of CPU to spare on our 
iSeries?

--What we are looking for is the ability to access remote tables as local 
tables in order to eliminate real-time replication requirements.  Is this 
really possible?  Can you do this with acceptable performance? Could we replace 
a PF (Table) on the iSeries with a link to a table in Oracle (without rewriting 
a bunch of old RPG programs)?  Any difference in performance between Oracle 
link to DB2/400 and DB2/400 link to Oracle?    

--Does the Oracle TG products offer $35,000 with of improvement over the 
capabilities of the Generic Connectivity option?  I realize that the TG option 
include bidirectional access whereas the Generic Connectity option doesn't.



Thanks in advance,

Charles Wilt
iSeries Systems Administrator / Developer
Mitsubishi Electric Automotive America
ph: 513-573-4343
fax: 513-398-1121