ECI cylinders
I've had 6 ECI cylinders (2 are still on) on my Mattituck overhaul exchange O-360 A1A since 1998, and all have been subject to ADs for cracking. None have failed, however, and the ECI Titans now on my engine have gone 800 hours over 12 years with compressions in the low 70's. The rear cylinders are Lycomings installed in 2001 which now have 1200 hours over 16 years with compressions in the middle 70's.