Radeon: higher model or higher sub-rank?

[peekaboo]

I see different Radeon sub-ranks (SE, Vanilla, Pro, XL, XT, XT-PE) for every model but I also find that a lower model with a higher sub-rank can cost more than I higher model with a lower sub-rank.
For example:
1. SAPPHIRE RADEON X700 PCI-E 256MB
Price: $164.45 CAD
http://www.ncix.com/products/index.php?sku=15416&vpn=SP-X700-256-X&manufacture=SAPPHIRE

2. SAPPHIRE RADEON X600 PRO 256MB
Price: $176.70 CAD
http://www.ncix.com/products/index.php?sku=13385&vpn=S-X600PRO-256-RT&manufacture=SAPPHIRE

So what's better (not specifically these cards) a higher model or a higher sub-rank?

[tomster2300]

The higher model will be better than the subrank. A whole new line is faster while the subranks are just modifications of that specific card.