As much as I like third party grading and what it has done for the hobby (I think more good than bad), if I were you, I would concentrate more on the cards than the holders they come in. Even raw cards can be great as long as you buy from a trusted source. If you go to sell them in the future then you can think about the slabs. Why not just say "I want to collect a nice '34 set in EX to EX+ condition?" Don't restrict yourself to a TPG. Unless you want to collect plastic then that is my take. You might collect some nice, raw commons to start with. Get them in and handle and smell them
. You can research them on the net but.........There isn't a much better way of getting to know a set than handling them, imo. Good luck in your endeavors.