From 4 different brands of hearts and arrows (brian gavin, whiteflash, infinity diamonds, high performance diamonds), are they all so good I should just go off price? or are the differences important? I have heard 1 to 2 is preferable for HCA is 1.0 good or too low? compared to say 1.5
Some of the best stones in the world! You don't use the HCA with hearts and arrows ideal cut stones. All of these have superior cut and light performance!
My personal experience is with WhiteFlash ACA's, and that will normally be my choice if they have what I want and the price is right. Their prices sometimes are lower than the other two you've mentioned. There is an additional PS/wire discount there, too. I also like that the crown angle of #3 is 34.4 as I'd rather have a crown angle that is a little higher, not that you can see the difference in these in real life.
Are the color and clarity all the same? Because the diamonds are all superior, so you need price and specs to make the decision for you.