It's not worth paying the extra bucks for the memory. Even value ram does decent job. Check this
Corsair wouldn't be worth it. If I were buying a bit better memory for a64 system I would buy Crucial Ballistix pc-3200. It's gold editor's choise
in anandtech does incredibly well as shown in the first link.
And the best part... 2x512 would cost you only 1750SEK (193e) including shipping. I live in Finland and even the crappiest memory here costs quite much so next month when I am making my upgrade I think I will order Ballistix pc-4000 would be a cost maybe 90SEK (10e) more.