A lion in a 35 is not the best choice in the world, especially if you have a high tank. Lionfish like room to swim horizontally. A fuzzy dwarf CAN get to be about 7", like already said above. A fu manchu however will only get to be about 4" in size, but I know from personal experience that lions do not ship very well.
If you can find a good Fu Manchu or Dwarf Lionfish that has been at a LFS or supplier for more than a couple days (I prefer a week), then get it for your 35. Fu Manchus are a better choice than the Fuzzy Dwarfs because they stay smaller, but the benefit of having a Dwarf over a Fu Manchu is that Dwarfs are easier to get on a frozen rather than live diet.
It's your call in the end, but I definitely would not get any lion for a 35 that is not already passed his shipping stress. Lions suffer a lot of stress from the shipping process, and sometimes, they are even caught via the cyanide method. This is why you need to give it sometime to see how healthy and stable the fish is before you purchase it. Once lions get passed the shipping stress, they are a very hardy fish.