Stock heads are what come on the bike from the factory. For 05 they are changed from the earlier heads, something to do with the valve guides and stems. I think the jury is still out on what can be done to them perfomance wise. The next step up is the SE heads, they flow better than stock but most folks feel they should be "cleaned up" by someone who knows what they are doing, like SMB. Next on the SE food chain are the HTCC non ported heads. They, in combination with a cam of 240-250 degrees are designed to have good torque and over 100 HP from a 95 inch motor (or a 103 for that matter). Next are the heads you are talking about, the SE103 + heads and matching pistons. They will flow better than the non-ported HTCC heads and have a "hemi" style combustion chamber much like what you see on the Jims 120 motor. They are nicely complemented by again a cam like the Andrew TW55. The best flowing head is the HTCC CNC ported heads. They will work with your SE264 to give great top end, but at the price of less torque at the bottom and midrange. You will have to rev the motor to get the most from it. Just remember, you don't ride a dyno and great dyno numbers don't get it done on the street in most instances, especially with a heavy bagger with one or two up. I have played the head/cam game a number of times and can tell you true, the more conservative cam is the way to go for a street bike that you will like to ride. The Harley Tech Board can be found a "Harley Tech Talk". Ride safe. Spook.