I love Mathilde's ring and wouldn't turn down the rock that Sophie is wearing either.
Yea If I must I'm willing to take Sophie's too

According to this blog
Sophie's ring features a 2.05-carat oval diamond, flanked by two smaller heart shaped gems, set in 18 carat white gold. Made by the Crown Jewellers, Aspry and estimated at £105,000, it is said to be the most expensive royal engagement ring in history.
http://marilynsroyalblog....yal-engagement-rings.html