FYI...Been a trap shooter for many years, also do a bit of skeet, tower & sporting.
Never really saw the advantage of the high rib, UNTILL' I tried one..attached a pic of my now Trap gun...certainly feels more comfortable & hoping I get some consistency as been all over the place recently. The gun is a Spanish FS 400 Sarriugarte which I bought new in 1989 & have used in ISSF Trap [ even shot a possible ] . It had been in the safe & not being used so I started to shoot with it again & decided to put the high rib on.The rib is the 'add on brand..16'' inch adjustable 20mm [3 / 4 '' ] high
Gun is a side lock ,mechanical trigger with fixed 3 / 4 & full chokes.