3ware Escalade 7810 vs 7506-8?

[mpeg4v3]

Last week I purchased what I thought would be a 7500-8 off of eBay. It arrived today, and *looked* like a 7500-8, but upon plugging it in and powering it up, it's detected as an Escalade 7810. I can't really seem to find too much information on the difference on google, but from what I can tell, the 7500-8 adds some sort of R5 Fusion function to the controller for better RAID5 performance. Since I'm going to be doing RAID5, this is important to me. So I had some questions:

1. Does anyone know the performance difference between a 7500-8 and a 7810?
2. Would anyone with a 7500-8 and/or 7810 be willing to give some benchmarks? Namely I'm wondering about Sequential write and read, as this card will be in a file server.
3. How would the performance be vs. a Promise SX6000?

Also, when googling, I found some decent res pictures of the 7810 vs the 7850... which to my understanding IS the 7500-8, just with the name it used to be called.
The 7810:
http://www.xbitlabs.com/images/storage/3ware-7810/card.jpg
The 7850:
http://www.xbitlabs.com/images/storage/3ware-7850/controller.jpg

The thing is, my card looks like a mix between these two. For example, the component layout is *identical* to the 7850 (despite the fact there aren't many differences between the two), HOWEVER, my card uses the same smaller size RAM as the 7810. The bios detects it as a 7810, but I was wondering if many anyone had any ideas on to whether this may be a 7850 in disguise? Or if I should just get the guy I bought it from to refund me?

Thanks!

[Lazn_Work]

The fact that the card layout changed is not suprizing, 3ware is not a huge manufactuer and I am sure they share designs between models as much as possible. So when they needed a new layout for the 7850, they just used that for the last of the 7810's, in other workds they used up the last of their 7810 parts on the new board layout. (so you have a very late 7810, a few days later and it would have been a 7850)

Was it sold - advertized as a 7500-8 or 7850? If not, keep it.. there is not a huge differnce between them. But it really is up to you.

==>Lazn

[mpeg4v3]

It was actually advertised as a 7506-8- slight typos in my original post due to all of the different model numbers I've been looking at. The guy said it was a 7506-8, and when I received it, booted it up to find a 7810. I called 3ware tech support and they said that whatever the firmware said while booting, was what it is. I've already asked the guy for a refund, and I'm going to try and get an actual 7506-8 this time.