Its tough but I'd probably say Ellusionist in terms of cardistry because they offer more variety in their XCM section. Other than Theory11 which only has 2 dvds on cardistry.
Overall Ellusionist has more variety in everything compared to Theory11.
Not to add fuel to this fire - as I feel it's a bit apples to oranges - I did want to clarify this point. I'm not sure which videos you're referring to, as I counted a grand total of
four cardistry videos available today on Ellusionist. None of which were produced by Ellusionist, which is a point worth making if you're objectively comparing the two companies as content creators - not stores. This is not to say that those four are not heavy hitters - I believe xB and xB2 in particular are outstanding DVD's and some of the best that have ever been released in the cardistry genre.
theory11's cardistry products: Genesis v1, Dangerous - Motions, Trilogy v1, Trilogy v2, Trilogy v3, andthensome, Elevator Cut, b4cut, Cardistry 101, Backpack, Inflight, Static, Asybil, Rebel, and five other 1-on-1's derived from the Trilogy.
While it is true and valid that our overall selection is far fewer than most other online retailers, our production pipeline is second to none in both magic effects and playing cards - tricks and cardistry. It is our intent (not our shortcoming) that we focus on quality and not quantity, as the latter is provided by many other retailers already in existence. Providing more of the same doesn't excite us - we would much rather bring you selective, unique items (both videos and products like the 125's). And we do so as much as we possibly can.
In summary thoughts on this thread - I think to each his own. This is an artform with a plethora of great resources at your disposal for study thereof. There are countless books. There are countless videos. And there will only be more and more. What's important is not where you buy, but
what you buy - and the student of magic you become. One could argue that I am less than objective given my history (I was at Ellusionist for six years before resigning as President in 2007) - and my current role in theory11. I am completely transparent about that and in the interest of full disclosure, I put that on the table.
But I think that my point is valid and my conclusion is sincere. We try to be the best we can and work with the best creators this industry has to offer, but we would be naive to proclaim that we are, or should be, the only source for your education of an artform. Expand your boundaries, soak in everything you can, meet the greats, read, read, read. I guarantee that your knowledge, skills, and expertise will benefit as a result.