Has anyone had any experience with Rainier c4 rail mounted sights or Hayes research style sights? The Rainier's appear to be the same hight as a standard BUIS. The Hayes are lower and it would appear to give you a mp5 and or a sig 550 type sight picture. I have a ACOG TA31 RCO and do not want the sights to co-witness with the scope. The Hayes web site has been down for months and I have nnot been able to locate a set. Has anyone tried these sights?