My favorites have always been Eley subs. These have always been the most accurate in my .22rf bolt action rifles and I have tried most brands over the years. However, I recently bought a Theoben AMT semi-auto (stainless clone of a 10/22) and did a fair bit of ammo testing. The Eleys wouldnt cycle at all and CCI's and Winnies were not much better (The CCI's were unacceptably loud even with a moderator but very consistent velocity wise). I had some old RWS subs and these cycled well but were very low velocity with a noticeably lower POI. Then I tried some of the new RWS subs and these were higher velocity, cycled perfectly and I managed a 1/4" 5 shot group at 50yds -not bad for an old semi-auto! Well worth a try!
My chrono results through the AMT were as follows:
Eley Subs 932, 1004, 1015, 994 & 998 = Av 989fps Spread 83fps = 8.4%,
RWS (Old) 1014, 993, 978, 960 & 985 = Av 986fps Spread 54fps = 5.5%
Winnie Subs 1028, 1022, 1041, 1005 & 1030 = Av 1025 Spread 36fps = 3.5%
Eley Pistol Match 1002, 1008, 1001, 1003 & 1030 = Av 1009 Spread 29fps = 2.9%
CCI Subs 1066, 1063, 1057, 1054 & 1069 = Av 1062 Spread 12fps = 1.1%
RWS (New) 1017, 1013, 1018, 1028 & 1020 = Av 1019 Spread 15fps = 1.5%