Don't know what a 1201 Riot Gun exactly is but I've owned a Beretta 1201FP for about 5 years now. Upon delivery I immediately sent it off to Ted Yost @ Gunsite for a Gunsite Police Shotgun workover.
This consisted of shorting the barrel to a RCH over legal length, trigger job, shorting the stock, MMC Ghostring Rear sight and Tritium front and lightening the bolt release.
This has to be one of my favorite firearms. Quick to mount, fast to swing, easy to shot. The only problem I have with it is that my wife declared it hers after she fired it.
While at a gunshow this weekend I saw a 1201 that had a factory Ghostring sight. If this is the "Riot" Gun you speak of I don't think you will be disappointed with it.
Schmit, GySgt, USMC(Ret)
NRA Life, Lodge 1201-UOSSS
"Si vis Pacem Para Bellum"