For what you want to carry, no need for 20 version, unless you'd rather have extra space since the price is the same (10 vs 20).
Like I said, on the left I slide the 18-35 or 70-200 ; on the right I slide the 50 1.8 and all the hoods ; in the middle goes nicely the D750 with 24-120. One thing to note is with this setup, hood cannot be mounted on lens in the bag (even reversed). Hence, I keep them with the small 50mm since they all fit well one into another. A second 50mm would actually fit...
On top of that, I carry the weatherproof bag in the front pocket, battery, filters, cleaning pen.
Indeed, easy to switch lenses with that bag.
Another thing to note is that I find it lacks padding on the bottom specially, I could hear the lens knock the floor every time I deposit the bag.
I went to the camera store 2 hours ago to finally do some compare/contrast. Checked out the following:
Tamrac Jazz 78 Photo sling
Low Pro slingshot 202 AW
Tenba Shootout LE Sling (small)
Think Tank 10 and Think Tank 20 turnstyle
The Tenba was pretty nice but seemed somewhat tight. I did like the Low Pro but really wanted a sling where I'd have access to the body as well as the lenses. The Tamrac was a nice low profile oddly shaped bag that did not seem like it would be particularly bulky when full but again, somewhat tight.
The last bags I looked at were the Think Tanks...and it was immediately pretty obvious that the TT bag style was pretty special. The sling bag is very low profile (does not stick out much from your back), a nice teardrop style and amazingly small! The Think Tank 20 was smaller than the Tenba and the Low Pro. Most important, when you sling the bag around so it is in front of you, you can easily get to the camera and all of the lenses. I was able to put my D750 attached to a 24-120, the 18-35 f3.5-4.5 and 35mm f1.8 in the bag. I can even fit the 50mm f1.8G, an iPad mini and filters/memory cards/lens cleaning gear. The big question will be the comfort level when carrying the bag around. Not sure I'd be happy with the Think Tank 10...probably get a bit tight.
I'm really stunned at how small both bags are (the 10 and 20). Think Tank has a real winner with the Turnstyle bags (fingers crossed re comfort!)
Richard
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Current cameras: Nikon D750, OM-D E-M5, Panasonic G3, Sony RX100, Panasonic FZ200
Lenses: Oly 12-40 f2.8, Nikon 24-120, Nikon 18-35, Nikon 35mm f1.8 EX, Nikon 50mm f1.8, Panny 25 f1.4, Panny 35-100, Panny 45-150 and Rokinon 7.5 f3.5
Sold: Sony A7ii, Panasonic GF1, Canon S100, Oly XZ-1, Sony HX200V, Canon 60D
Returned: FZ1000
The 20, 10 and 5 Turnstyles:
