I still use a rear open sight. I've played with a few peeps through the years, not real parshail too'm. As most of my compitition is off hand or in the field, I 've found target aqusition time just a bit slow for my style using peeps. I can't denie they are more accurate off the bench.
I've used the above site on several T/C, because I prefer the slot style rear vrs V shaped. The near "drop in" size of this front blade makes it an easy fit, plus it's large enough to file down to what you want..you can even thin the sides down. I've tried brass and silver too. Brass can get ya in trouble if the light glints just right, silver kinda disapears for awhile in that dusk/dawn transition light. So I stick to iron for my target guns. If I know I'm going to be shooting in marginal light, I brush on a little White Out on the back of the blade..I can scrape it off with a knife blade. Iv'e gone as far as holding my barrel over a sooty candle just to take the shine off.