Hey bud, have not used the kits you mentioned, but have used the Dark Elf Corsairs and to be honest they are a bit of a pain. The cloak is the best bit but carving out the back half of the torso is a pain. The sheathed swords and knives are nice bits though, but overall you get more bang for your buck just pick up Kabalite Warriors or Dark Eldar Wyches. They've got sheathed knives, pistols etc which better represent things like Venom Blades and Brace of Pistols.
I picked up the Glade Guard spears too, but again they are held at weird angles and need to be attached to a seperate arm which is difficult.
I've found the High Elf Dragon Rider kits offer much more. Torsos, swords, heads, banners etc which are very helpful not to mention the excellent lances. The same can be said for the Cold One Riders which come with some very nice lances, banners and the Cold Ones which are a natural fit for the Exodites.
Honestly the Dark Eldar range is the best for conversions. Wych running legs, guns, knives, alternate heads, alternate legs which all mesh great with the Guardian kit. You can even order big bunches of heads, legs etc for 10 bucks a pop on ebay.
Anyway hope that helps good luck buddy!