Tamron: I don't like them, period. Generally considered to be at the bottom of the genepool of lensmakers.
Phoenix: down there with Tamron. B-name brand of Sigma for low-cost retail chains. Similar design but lower quality optics to the cheaper Sigma consumer models.
Stick with Tokina ATX or Sigma EX lenses for optimal quality unless you can afford the AF-S Nikkors or L Canons (or the equivalent pro line of your camera brand).
Tokina was indeed started by Nikon lensdesigners with the explicit goal of creating lenses that are of almost equal quality to Nikkors at a substantially lower price. At this they've succeeded.
They do get their glass from Hoya, who are also the source of glass for Canon (so if you say Tokina uses inferior glass remember you're saying the same of Canon