Using the effect from a magic item as a feat prerequisite?

[Fredison]

If a magic item grants my an effect that is for all intents and purposes permanent, can it allow him to qualify for a feat he normally couldn't otherwise?

Specific example: My bard gets himself a Wayfinder slotted with an Opalescent White Pyramid Ioun Stone, giving him Weapon Focus (Light Crossbow). Could he, then, qualify to take Dazzling Display next time he gains a feat from levelling?

[Starglim]

Yes, but he only benefits from the feat when he meets its prerequisite. If he takes the ioun stone out or walks into an antimagic field, he can no longer use Dazzling Display or any further choices that depend on that feat.

[Fredison]

All right, I figured as much but it seemed iffy. Thanks!

[Jaxtile]

If you wrap the wayfinder in lead, is it immune to AMF?

[kinevon]

Jaxtile wrote:

If you wrap the wayfinder in lead, is it immune to AMF?

Since the lead prohibits you from gaining any effects from the wayfinder, what does it matter?