Any SGI/Oracle evaluation experience?

We are currently evaluating our options in moving some existing Forms 3.0-based applications running against Oracle 7.1 from RS/6000 & AIX to SGI Challenge. While we could be evaluating HP, SUN, DG, et. al., we are centered on SGI for a variety of business partnership / political reasons. We are interested in feedback from anybody that has either worked with Oracle and SGI, or has been performing similar analysis. Our simple findings thus far:

1. SGI Challenge performance, in a SMP / Oracle Parallel Server configuration significantly outperforms RS/6000 equipment
2. SGI Challenge systems appear to be significantly less expensive, when compared to IBM RS/6000 systems. Given that IBM can not compete on the highest end of performance, save for the SP2, comparing "apples to apples" is sometimes difficult in this criteria.
3. SGI appears to have worked very closely with Oracle in developing some key Oracle-specific features, like dba - database accelerator, that improve Oracle performance dramatically.
4. SGI lead times for delivery of equipment are significant better, in real world terms, than IBM's. (2-4 weeks compared to 6-10 weeks)
5. There appears to be some concern about SGI IRIX and its stability, especially as compared to the commerical robustness of AIX. Specific examples from SGI/Oracle users and DBAs would help here.
6. While SGI is a contractual tier one Oracle port, everyone who works with Oracle knows....Oracle works with platforms that bring in the revenue. Will SGI achieve status with HP, Sun, and IBM?
7. Does IRIX have the system management capability and functionality that IBM and AIX have?
8. Can SGI's service, support, and consulting rival IBM's in a mission-critical, commercial database application environment? Can SGI provide the level of hardware and software service that IBM does?

As you can see, this is a tough decision for us. We are looking for a system capable of supporting a mixed OLTP / Batch environment with heavy month-end processing (accounting applications). We have requested a configuration of minimum 4 processor, 1 gig memory, 50+ gig of RAID5 storage, high speed backup. We are looking at high availability options as well.

Any thought or ideas from AIX, SGI, or especially shops where both SGI and AIX are used in heavy Oracle RDMBS work would be very much appreciated.

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Scott M. Langdoc                                       scott_at_uscs.com
U.S. Computer Services / CableData
Rancho Cordova, CA  95670