Hi, Rainbowfire!
As you've probably seen from other recent posts, Rider Waite and the clones do have a lot of fans, but I'm not one of them. I do agree with Destinyawaitsme in that it does seem to be the deck which has the largest amount of backup material.
I, too, have Shapeshifter and would agree that it could be a very difficult first deck. I also have Spiral and use it quite a bit. I find it similar enough to RW to use the books written for that deck. I do also have the book written by the artist of the Spiral which gives in-depth background for the Major Arcana, which I find extremely useful: for instance, when the Hanged Man came up recently, it popped into my head (which is how I get my best results) that it was based on Dionysus (the Greek god of wine) and so joked with the client that she must have turned to alcohol at one point - and she confirmed it. Not exactly a traditional reading, I believe! The detail on the Minor Arcana are more sketchy (and as it says in the review on this site, the artwork could be by two different people) but most of them bear a marked resemblance to the RW deck. However, I go with what the picture indicate to me, rather than what the books say.
My all-time favourite deck is the Osho Zen. It has keywords printed on every card (a handy pointer if you're just beginning and having difficulty in remembering all the meanings) and the artwork is very clear - although certainly not traditional. It has coloured and numbered diamonds for suits (grey is the equivalent of swords, blue = cups, red = wands and the rainbow suit is pentacles, which could take some getting used to). I find it really does "talk" to me, but I know there will be many experienced people out there who would be very wary of recommending it as a first deck.
I don't have any experience of the other decks you're looking at, but I'm sure there are many others who will help you out there.
All the best in your search.