I had a 0.56ct with a tiffany 6 prong setting. Look at my avatar, that's how it looked.
If done well, I feel that the 6 prong setting can give an illusion of a bigger diamond. However, the prongs shouldn't be too "thick" that they overwhelm the diamond.
What diamond specs are you looking at? If you are going high on colour and clarity (which was what I did initially), you may wish to consider lowering the colour to G/H with a clarity of VS2/SI1. That will give you a bigger stone for your budget while still being very close to colorless.
Lol.. what a coincidece.. F/VS1.. exactly the same specs I had, only slightly bigger. For a VS1, I would be looking for a "cleaner" looking hearts image.
If you like, I can send you the link to the diamond I had. I returned it to WF recently. It's now at AGS labs for verfication and should be put back up for sale soon. The diamond is a beauty and it was sad that I had to return it.
I'm from Malaysia and while I like Lazare diamonds, they are about 50%-70% higher in price than ACAs. Same goes for Hearts on Fire. And there's no guarantee that Lazare / HoF will come with perfect H&As unless you sit in the store the whole day and look thru them one by one thru the H&A viewer.
ACAs are a better alternative for me, though as with all online purchases, there is always the risk that comes with having an item mailed to you.
If you are concerned on the size of the diamond, I would suggest that you check out in person how a stone of that size looks in real life.
justin.. if you are still on this forum, one thing you probably should know is that there is an import tax of 10% for mounted diamonds, as opposed to no tax for loose diamonds.
When I purchased my previous rock, I bought it loose and had it set locally to avoid being taxed. I wasn't sure if one ring will attract any tax but I didn't want to chance it.
However, having it set on your own also has its risks. Most B&M shops in Malaysia are not willing to guarantee against damage to your diamond during the setting process. Some would even ask you to sign an indemnity letter before they are willing to set it.