I have questioned this before and I am with "RAYGE" on this.
There doesn't seem to be a way to set products up in VM3 with full stockable control? IN VM2 we used the stockable variants plugin, which no longer exists.

The Santa Cap in the demo (
or the "Product using generic child and cart variant" in the sample data) will functionally work to a certain extent, but this doesn't allow products in this setup to be stockable as the stockable variants plugin worked in VM2.
Say you have a Red & Green T Shirt's in Small, Medium & Large.
You can set up a product called T shirt & then 2 children named, Red T Shirt & Green T Shirt, then use the "Generic child Cart variant" against these.
In each of the Red & Green T shirt you then need to used the "Cart variant" to add the sizes - Small. Medium & Large.
This gives you the equivalent of the Santa Cap, but then none of the products have stock control.
Also when selecting the Generic Child variant the URL changes and the page refreshes. I understand that this was done to allow you to display different images for the variants, but is there a need to reload the page & change the URL.
Balai, I would be interested in having a look at your stockable variant plugin & testing it And think there should be another option in VM3 for fully stockable Parent/Child products
Ideally what I want/need to do is (using the above T shirt example) is to set up Parent Product called T Shirt, which doesn't have to be orderable. Its almost a place holder & then create 6 Children products as below - Where in these children all I need to add is, Price, SKU, Stock Number, weight, Image
Parent - T Shirt
Children;
Red T Shirt Small
Red T Shirt Medium
Red T Shirt Large
Green T Shirt Small
Green T Shirt Medium
Green T Shirt Large
Then some sort of stockable variant plugin that will allow for 2 dropdowns in the front end, one for "Select Colour" & another for "Select Size"