These two castles are both built with the system-X, but 3268 costs 25-50% more - so is it worth the extra cost?
The bulk of the castles are built from the same components, and the colour of the stonework is the same, so these units can easily be combined to make a mega-castle.
The main difference is that the 3268 set incorporates a domestic side, with a (Count or King or Baron) and his lady, and a herald, living in a keep - with an outside garderobe (medieval toilet) and a stable underneath which may be intended as a dungeon, and a falcon and a dog for hunting. The drawbridge on the 3268 set doesn't have the breakaway portion, though there is still a breakaway wall section.
The red-tiled roofs give it a more cosy feeling, but I dislike the blue doors and windows - I'd refer a generic castle which I can populate with my chosen band of knights, and I'll replace the blue windows and doors with direct order spares in time.
The magnificent gatehouse with drawbridge is the same in both sets.The red clip-on tops in 3268 give the guards a little more comfort, though they wouldn't last long in a siege.
The box pictures for 3268 do not show that the back of the keep is open, so you can play with figures inside.
If your (inner) children only play battles, then the Eagle castle has everything you need. If they want to recreate the domestic side of castle life, then the extra features of the larger set are useful.