Many dealers will send a stone to him before you even pay for it. Then, if you like it, you pay. Based on the table and total depth the stone is belong to 2A AGA class which is very good. See if you like the larger appearance of the diamond you are thinking of compared to the extra, invisible depth on those. The, look at the table.
Larger tables decrease the dispersion effect around the upper perimeter of the stone.
Some prefer it, but many would not once they are clued to what is taking place. You need at the very least to know the crown height percentage. But, without the crown height, you are not going to know a whole lot. Hope this helps and does not confuse you further. In the end, you buy what you like, not what we tell you to buy.