I get tingling and numbness on the first two fingers of my left hand because I have cervical spine stenosis (resulting from arthritis in my neck). I minimized it by physical therapy and then doing the exercises religiously. It has made a greater difference than any changes I made to my bikes.

I have two bikes, a drop bar and a flat bar. I have Ergon grips on the flat bar bike and like them a lot. I don't even wear gloves on that bike for most riding. They are quality grips. However, before I did PT for my neck even with the Ergon grips I would have problems develop with numbness about 20 miles into a ride. I also put aero bars on that bike to help me with changes in position which would help neck pain and numb hand. So for me it wasn't a cure. But I wouldn't give them up because they are so comfortable. Now after PT I dropped the aerobars and am riding both bikes fairly comfortably and can do 50 miles on either bike with no issues.

I guess what I am saying is that it might depend on why your hands are tingling or numb. The grips might help a lot if it is a carpal tunnel issue, but if it is a pinching nerve elsewhere they may not help much.