I don't know for sure, but it looks as though the clock speeds are the only difference. That being so, you can overlcock the non-AMP to the clock speeds of the AMP, but I'm sure you could also overclock the AMP further than the non-AMP; because that's how they determine which is the AMP, they are binned higher and can perform better. Although the difference there could be so small as to be non-evident.
If I were buying an RTX 2080 Ti, I would wait for the upper tier models to come out; such as the AMP! Extreme which typically has better power phases and a larger cooler. But, I already have a good GPU so I can wait without much anxiousness. I don't think I need a GPU that costs that much anyway. So, I guess it's up to each person what they need.