Very helpful! Didn’t know you could be super ideal without the H&A. Would you recommend finding stones with both AGS and GIA grading for stones this size or should AGS be sufficient?
I'm sorry this is so long...if you asked in Pricescope though, the thread would go on for several pages....so think of this as the synopsis of the answers you would get there...
You could honestly do either one. Percentage-wise there are a lot more (a whole lot more) stones out there that have GIA certs because it is the biggest lab with the farthest reach. Downside is you are going to probably have to do all the grunt work on your own (running numbers and viewing stones) because GIA XXX is a fairly wide range, and just because it makes GIA XXX does not put it automatically in AGS Ideal parameters (proportions). You could consider Ideal parameters a small subset of GIA XXX. Now, I think (but would have to check) that AGS 000 stones most often (I suspect there are some borderline cases with them as well, but don't know) will fall in Ideal parameters. Since AGS grades on light performance and 000 is the best there is, most of the Ideal/Super Ideal cut vendors (eg- Whiteflash, Brian Gavin, August Vintage/Good Old Gold, Crafted by Infinity, Victor Canera...etc...) use AGS for stone cert. But note they are all in the US, and that is where AGS is located so I think that is mainly why you see AGS certs here and not elsewhere. They've done all the work for you on their in house stones (their "brand" stones) so you don't have to. If they've put their laser mark on it, you already know it s good.
If you are in the US, my suggestion would be to go with either Whiteflash or I think also CBI (Winks brand) as they have the absolutely easiest upgrade policy. Basically, just spend more money...no double this, no improve on that...just spend more. But, I also think that Jonathon (of Good Old Gold now his own brand August Vintage) may have both GIA and AGS certs stones. The big bonus with Jonathon is that he is a real trail blazer and has been cutting Lab diamonds in Ideal specs, and so they cost less because they are lab created (ie- real diamond material, grown in a lab not a synthetic) but I do not know his current upgrade policy but also have been vetted by him for performance.
Now, the branded ideal/super ideal cuts are going to cost more than Blue Nile or James Allen, but all the grunt work has been done. So if your goal carat size is out of budget, do it in parts. So, my suggestion is if you go with WF or CBI, get something in your current budget if it is too small to reach your goal size/weight, knowing you will be trading up to a larger size when you can. The most you lose is any sales tax and possibly the setting cost if you are in their state because you get to apply the entire purchase price to the upgrade.
Sorry it was so long! To me, a diamond purchase should take some thought, just as you would when considering a really expensive purse, or a car....
And you absolutely can have a stone that hits AGS 000 without it being branded H/A (since H/A is symmetry and not light performance). Here's my (current) stone, a Brian Gavin Blue (fluorescent line- I love fluo!) branded stone. I have no idea if it makes H/A symmetry as I've never seen it unset. It would need to be face down to view the hearts and was not marketed or sold as H/A but it is a branded Ideal/Super Ideal stone:
but page 3 has some very important discussion by John Pollard (diamond designer) and Karl K.