I submitted a similar post on Drupal.org too - http://drupal.org/node/318796 - but i don't expect much feedback from there (because there's always a lot of new posts and it's easy to get pushed down to oblivion).

Well, i will be posting in this thread as i test and find out how Ubercart works on this area. It will be good for further reference (for me and others).

In the start, Attributes and Adjustments looked great for my case.

As it says on the Documentation:

There is a SKU adjustment system available through the Attribute module that may be used to alter the product SKU depending on a customer's attribute selections. Once you have attached attributes and options to a product, go to the Adjustments tab on the product edit page to alter the SKU when a particular combination of attribute options are selected by a customer. When the product gets added to their cart, it will contain the adjusted SKU.

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But i have discovered two things on the way Attributes are managed:

1) In my case only colors should define the SKU. Sizes are irrelevant.
But custom SKU's are setup by comboing all the attributes available for a product, even the ones i may consider irrelevant for my SKU scheme.

So if a product has 10 Sizes and 3 Colors, i have 3 SKU's. BUT, i have to fill the SKU fields 30 times!

Note: i dont mean i must have 30 different SKU's. I mean i still have 3 SKU's but i have to fill it 30 times. Quick example here: http://uploads.screenshot-program.com/my.php?image=upl6067853938.jpg

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2) On the Product Edit Adjustments page ( http://your.site/drupal/node/xxx/edit/adjustments ) you learn that: Warning: Adding or removing attributes from this product will reset all the SKUs on this page to the default product SKU.

At first i was a little worried. Let's say i want to add a new size (example: new tshirt size XXL) - will that reset all the SKU's?

The answer is no, that wont reset it! I was confusing Attributes with Options So adding a new option (a new size option) wont reset the SKU's.

But adding a new Attribute (a new set of options) like for example "Quality: Regular, Special, Super Resistant, Adamantium-Coating, Kryptonite-finishing" then it will reset all codes to base SKU!!

This means you gotta plan everything very very well! Specially if you're dealing with thousands of products (not my case, i'm in the hundreds but still).

Choose your approach by the way your customers will probably surf through your shop:

I'ld put colors and sizes as attributes, make product types, categories, age, brands and gender available as catalog blocks and/or make view filters for categories, age, brands and gender.