I have a Manfrotto 3246 with 3047 head. The legs are sufficiently heavyweight for an 8x10 but I am not a big fan of the head design, and the hex plate doesnt seem as secure as I would like.

-I always thought a gitzo 1570 head would be perfect, but I never had the chance to try one out.

I also have a antique wooden miller tripod, probably designed for a cinema camera. Similar to this but with a flat plate and a 1/4 tripod screw. No head at all, I just raise or lower the legs for a little bit of tilt. Loosen the tripod screw for pan. I cut out a circle of cork to protect the wood of the camera from the metal the head, but I think rubber gasket material would work better. Easily handles 8x10.

For 35mm - 4x5, I have a manfrotto 055xPROb with 804RC2. I like the lever locks on this better than the twist lock on say a tiltall. Again, the quick release plate seems to be a point of instability, but I have learned to live with it.

I have had a Tiltall before ( a later version). The integrated head is better (for large format) than most other pan-tilt heads imho. There is no quick-release plate, only a 1/4 inch standard bolt. (though this requires some force to tighten enough for a heavy camera/lens) The pivots are stacked right on top of each other and completely centered. But I was having problems tightening the legs enough, or too much. The lock rings really need to be larger, or have a tab for more leverage. Perhaps the earlier versions are better in this respect.