I am looking to upgrade my wife's engagement ring (ACA WF .8 E SI1). My range is from 1.5-1.8ct depending on the grading. I am normally an e-ring buyer but I was shopping around and noticing that a lot of the retailers have dropped their prices. I am currently looking at two diamonds from Michael C Fina 1.5ct F VS2 HA (13.5k)and a 1.74 G SI1 (non HA but a very high quality diamond) for 17k both with excellent cut, symmetry and polish. Knowing that this is the second ring would you go for the bigger diamond of good quality or a "smaller" diamond of excellent quality. Let me know your thoughts!