I've got a new AS z1 coming my way and have ordered the custom plate for the d600 with grip and also the tripod plate for the 70-200 vr.
I'm now wondering about l-plate vs standard...
My gear is: 16-35 f/4, 24-70 f/2.8 and 70-200 f/2.8
For most of my outdoor tripod work I typically shoot in landscape orientation and as I will have the tripod foot for the 70-200 (it has the lens collar), I don't see an advantage to an lplate there for portait orientation.
The 24-70 I would most likely shoot hand-held for portrait work, but can see that I may wish to use the tripod. The 16-35 would again likely be in landscape orientation, but I can see that I may wish to have the flexibility to go portrait too.
Thinking about the above, I can't make a compelling case for the lplate (which is a LOT more expensive that the standard) as it seems to me that the ballhead should have little difficulty with either the 16-35 or 24-70 in portrait orientation using the drop slot.
Having said all of that, I've been wrong before, so would really appreciate your insights.
The L Bracket would not benefit you when using the 70-200 since the lens would rotate landscape to portrait using the lens collar.
Where the L Bracket would come into play is when you are using the collar less lenses like your 16-35 or 24-70. The advantage of the L Bracket is that is allows you to go from landscape to portrait without dropping the ball head clamp into the slot. The L Bracket allows you to keep the camera/lens combo centered on the ball head which is more stable than hanging your camera/lens combo off the side of the ball head.
For me, I would never want to drop the clamp into the slot. I want the most stable setup possible for all my shots whether using my 500/4 or my 17-50. YMMV.
Something else not yet mentioned, but appro pro your interest in strobes (from your profile), an L-bracket is necessary for external flash units, such as the SB-800, that are used with brackets such as the RRS Wedding Pro, bottom of page.
It really boils down to whether you think you'll use the vertical orientation enough with non-collared lenses like your 24-70 and 16-35 to make an L bracket worthwhile. I live in an urban area and a significant percentage of pictures I take are in portrait mode, so for me it's a no-brainer.
One thing that's worth mentioning: While it's true to that you can use the drop slot in the ballhead to frame a vertical shot, you may find that you have less range of motion / more restrictions on framing when the ballhead is so oriented, which can make composition a @#%&! (and the AS ballheads add an extra component of difficulty as the elliptical ball shape makes the motion stiffer the more you tilt the ball). For occasional use, it's likely something you could get along with.
>> and the AS ballheads add an extra component of difficulty as the elliptical ball shape makes the motion stiffer the more you tilt the ball
Years ago I tried a B1 in the field and came to the same conclusion- the elliptical ball was too much of a good thing, in that it was too stiff at extreme angles.
Some time later I briefly tried a Z1 in the field. I specifically looked at that, given my experience with the B1. The Z1 seemed much smoother at even 90 degrees (portrait orientation).
Having only tried an A-S head those two times, I don't generally mention this, but you may want to try a Z1 if you can to see if there has indeed been a favorable change. And anyone owning an Arca head should chime in too, of course. It's been somewhat of a mystery to me.