I use the Rider–Waite Tarot because they're closely tied with teachings of the Hermetic Order of the Golden Dawn and the symbolism is significant to me. I only have one deck, and I love the quality for how beautiful it is (gold embossed BUT thick/waterproof at the same time, meaning I can abuse them during my energy clearings)
I am always tempted to look at the really pretty decks but those are just pretty, less functional for my purposes