Sorry for the delayed response Lawrence, I have been waiting until I had time to sit down in front of a real computer.
Well I don't have any of those lenses I mentioned so I can't comment on them from firsthand experience, but they seem well regarded going by comments I have read on this forum over the last few years.
Here is a link to Dxo's reviews for lenses for the D7100 -
Best Standard zoom models for the D7100 - DxOMark There are links to there other tests for the D7100 once you are on their page.
The Sigma 50-150 is at the top of this list,
Best Zoom models for the D7100 - DxOMark
The Sigma 17-50 f2.8 rates highly in their tests. Interesting that they rate the Nikon 16-85 only slightly better than the 18-55, I noticed a big difference when I upgraded to the 16-85, which I am still happy with. Though I have thought about selling it for one of the 17-50's as I think they would be a better lens, but I would lose the longer range.
There is a member on the forum using a Sigma 18-35 and a Sigma 50-100 on a D500, he posted some good looking shots, I am sure these lenses would perform great on a D7100 as well.
I must say I have been tempted by these new lenses, but am hesitant to buy them because I can't rule out getting an FX camera at some stage and would rather have good glass to suit that system and I don't have the money to buy twice.