There are Thoth type decks, and there are Golden Dawn type decks. There may be superficial similarities in the overall artistic ambience (for want of a better word) of the two types of decks, but they actually are quite different, the model for the Golden Dawn decks being the card descriptions in Book T, whereas the Thoth decks tend to base their Trumps more on the original Thoth deck, which itself represents a further evolutionary development (perhaps including occasional mutations) of the Golden Dawn images.
If one is new to the Thoth system and doesn't particularly like Frieda's artistic style, they may look around for a similar deck having images with which they have a better rapport. If they plan to use the deck with a book keyed to the original Thoth deck, it would be much less confusing to use a deck which has the original Thoth structure, the litmus tests being the numbering of the Trumps and the Hebrew letter attributions of Star and Emperor. (These may seem superficial, but actually they are significant factors in Crowley's very meticulous development of the Thoth.)
In short, if one is interested in learning the Thoth system, I think it would be best to use the original Thoth. If that is not satisfactory for any reason, use a Thoth "clone," i.e. a deck having the Thoth structure, with images thematically based on those of the original Thoth. A third possibility would be a Golden Dawn deck without the specific Thoth structure, but I think this third option could be somewhat confusing unless one already has at least a superficial grasp of the Thoth system.