Is this what diamond shopping is like?

[monipod]

OP already mentioned that this is a one off purchase and upgrading is unlikely.

Then definitely a pair of WF beauties.

 

[monipod]

I'm trying to decide between two sets:

Set 1:

Diamond | 0.736 ct I VS1 Expert Selection Round Cut Loose Diamond AGS Certified | 4419249​

This fabulous 0.736 carat Round Ideal cut diamond has a clarity grade of VS1 and color grade of I.It is an excellent choice for engagement rings. | 4419249
www.whiteflash.com

Diamond | 0.744 ct I VS2 A CUT ABOVE® Hearts and Arrows Super Ideal Round Cut Loose Diamond AGS Certified | 4410606​

This Whiteflash A CUT ABOVE® super ideal cut hearts and arrows 0.744 carat I color VS2 clarity loose diamond is graded by the American Gem Society (AGS) Laboratories. | 4410606
www.whiteflash.com

I know it's trite and no one will likely be able to tell the difference but I would choose two ACAs sorry. If you ever want to sell them, those who want some WF studs might be put off by only one stone being an ACA. JMHO