Over the years, I've sat in:-
Dunlop - 1990 and 2007
Maison Blanche - 1992
ACO (or whatever that is called now- 18?) - 1993
Lagache - 2003
T34 - Pits - 2004-2007
Tertre Rouge - 2006
For me, I wouldn't go anywhere else but T34. Whilst there are limitations to the view, it is (by far) the best place to watch the pre-race festivities (which I love) and its a great place to watch at night. As a photographer, you also have the enormous benefit of no debris fencing to deal with. You can also hang over the barriers (after the first couple of hours) and get some good shots. So its definitely T34 for me for the foreseeable future. (The drawback this year was the pig's ear the ACO have made of access to the stand - I seemed to be walking miles toreach it this year......
).
Having said this, for the last two years I've been greedy and have had two seats. Tretre Rouge last hear and Dunlop this year. Both are OK but I didn't really make enough use of them to justify the expense. If I was to get a second ticket next year, I would want to try Maison Blanche again. In 1992, it saved me from getting very wet (most of the race) and afforded an excellent view.