How does it perform in person? It looks like it will be very sparkly around the edge and the very middle but not so in the area between the two in your pictures. Please view it away from the jewellery store lighting which can even make frozen spit diamonds look good.
I viewed it outside the lighting and it was very lively as well. To my surprise i couldnt find the inclusion which made it an SI2 so i figured its a great deal for the size and liveliness of the diamond.
As a cushion lover and consumer I would not feel comfortable buying a diamond without seeing an aset image which tells how well the diamond is cut and how it reflects light, and how it will perform. Its alot of money to put down to only later find out the diamond does not perform well.
Can the vendor provide aset images?
If it were me spending that kind of money on a diamond, I would need aset images.
The images alone don't appear too flattering. I'm guessing the ASET images will indicate a few larger facets around the edges with a crushed, icy pattern mix near the table. You have a pretty healthy budget and I'm sure the users here can find some pretty good options for you if you like.
Of course, cushions are all very unique so try to study up on the various differences between cushion faceting and identify which patters appeal most to you.
I looked at many cushions before I decided that I preferred chunky facets and a very symmetrical look, in a rectangle. Have you seen many cushions in person?
Do you like the sparkle pattern you see in this stone? That's what you'll see every day.
Go with what you think, not with what the guy selling it to you thinks.
Good Old Gold has very well cut modern cushions. They don't have much in your budget range at the moment, but you can call and see if they can access others.
I personally like the cut of this one better. If you've seen it in person or on video and like it then that makes it a contender.
I don't think that strong blue fluorescence is a negative. Some vintage stones where marketed as "blue whites," and it was a positive thing. You will ALWAYS be able to ID your diamond when someone does work on it and hands it back to you. If you carry a black light. But go with what you like and are comfortable with.