Ram Issues - First Gen iMac G5

Question

So here's the situation:
I bought 2 matched 1gb sticks of ram. I installed and my computer crashed, so:
1. i ran the apple hardware test - result: bad memory
2. I replaced the old memory - result: A-OK
3. Re-installed new ram 1 stick at a time, ran hardware test - result: Error, then OK
4. Booted each of the new ram sticks as the only installed memory, ran Rember - result: 1 bad, 1 good
My iMac is running on the 1 good one currently, and it runs just fine. no issues whatsoever. So i sent an email to the vendor saying "hey, one of these is bad, we need to replace one..." and got back a letter saying "oh, this isnt compatible with your imac, it won't work, pay us an additional $60 and we will upgrade you to ram that will."
Clearly, they did not read the email I sent that included the memory test results. Here's the kicker, they claim that they "checked their database, and then checked google, just to be sure" and the result is that it is incompatible. As I write this using the "incompatible" ram, I find that a tad hard to swallow.
Here's the rub: they give me the option to send the memory back, and they will "test it" and send me a new one if it is defective. If they are unwilling to read my email, what's to say they won't just say "yeah it's fine" and try to charge me some huge fee? Any advice or insights?

Answer 1

In short, I specced the ram. It's listed as a 128x4 density - however, there is nothing that says it would be incompatible, and in fact, my iMac is running off the ram. Figured I'd copy and paste the Rember results here:
the bad:
MacOS X (Darwin) running in multiuser mode
POSIX version 200112
Pagesize is 4096
Requested memory: 840MB (881750016 bytes)
Available memory: 840MB (881750016 bytes)
Allocated memory: 840MB (881750016 bytes) at local address 0x0000000004008000
Attempting memory lock... locked successfully
Creating test buffers...
Buffer A: 420MB (440875008 bytes) at local address 0x0000000004008000
Buffer B: 420MB (440875008 bytes) at local address 0x000000001e47b800
Running 1 test sequence...
Test sequence 1 of 1:
Stuck Address : setting 1 of 16ok
Random Value :  ok
Compare XOR :  ok
Compare SUB :  FAILURE: 0x8770b3a54dec9b40 != 0x8770b3a54dfc9b40 at offset 0x01baba19.
Compare MUL :  FAILURE: 0xbd556130c06fbbc0 != 0x1c04d21c951fbbc0 at offset 0x01baba19.
Compare DIV :  FAILURE: 0x00000001 != 0x00000000 at offset 0x01baba19.
Compare OR :  FAILURE: 0x9ebeb592ffffa087 != 0x9ebeb592ffffa086 at offset 0x01baba19.
Compare AND :  FAILURE: 0x1caa101048fb2007 != 0x1caa101048fb2006 at offset 0x01baba19.
Sequential Increment:  ok
Solid Bits : ok
Block Sequential : FAILURE: 0x303030303030303 != 0x303030303130303 at offset 0x01baba19.
Checkerboard : ok
Bit Spread : ok
Bit Flip : ok
Walking Ones : ok
Walking Zeroes : ok
* Memory Test Failed * Please check transcript for details.
The good:
Memtest version 4.13 (64-bit)
Copyright (C) 2004 Charles Cazabon
Copyright (C) 2004, 2005 Tony Scaminaci (Macintosh port)
Licensed under the GNU General Public License version 2 only
MacOS X (Darwin) running in multiuser mode
POSIX version 200112
Pagesize is 4096
Requested memory: 821MB (861085696 bytes)
Available memory: 821MB (861085696 bytes)
Allocated memory: 821MB (861085696 bytes) at local address 0x0000000004008000
Attempting memory lock... locked successfully
Creating test buffers...
Buffer A: 410MB (430542848 bytes) at local address 0x0000000004008000
Buffer B: 410MB (430542848 bytes) at local address 0x000000001daa1000
Running 1 test sequence...
Test sequence 1 of 1:
Stuck Address : setting 1 of 16ok
Random Value :  ok
Compare XOR :  ok
Compare SUB :  ok
Compare MUL :  ok
Compare DIV :  ok
Compare OR :  ok
Compare AND :  ok
Sequential Increment:  ok
Solid Bits : ok
Block Sequential : ok
Checkerboard : ok
Bit Spread : ok
Bit Flip : ok
Walking Ones : ok
Walking Zeroes : ok
All tests passed.