Often the average eye can not tell between ideal and very good. Plus these are in your ears..... I don't normally say quantity over quality but I happen to think the second pair are a perfectly fine quality for an earring. That said I guess my question is what kind of size would look best in your ear? If you have larger lobes I think you'll appreciate the greater ct weight so long as that weight is making the stone look larger. Honestly, I wear a sparkly pair of old round studs right now probably a little over 1 ct. They were my mothers and the quality is not great, they sparkle beautifully and are a good color but I can see a few inclusions for sure when I hold them in my hands and look carefully at them (not carbon). But nevertheless they were my moms and she has passed so I like to wear them now. I recently had them re-set in it this great 8 prong setting (they were in yg) that sit in your ear like a martini setting. They have so much sparkle and fit my lobes so well, I get tons of compliments from some of my pickiest friends, no one has any idea that they aren't a great quality.... and when I say not a great quality I will venture to say that the poorest quality you are looking at will blow mine away bar far. If you can look at these before choosing do it, try not to know which is which and see what you like best on.
I also have a pair of studs that my husband got me years ago as like a starter pair, they are also 1ct and probably in a similar quality category as my moms, I have screw backs on them with a different setting and wear them mostly over the summer when in the water a lot and when we travel now.... I have very little $$ invested in two pretty pairs and when I stand next to my girlfriends that have thousands and thousands invested in their studs you'll never tell anything other than we both have some sparkly diamond studs on..... For whatever reason, earrings are just such an abused piece of jewelry for me that I'm unsure a huge investment is necessary, but that's just me... I always thought I would upgrade from the first set my husband got me, but I love them and have so many other things I would rather do with the extra money now. Good luck, sorry for such a long story : )