What guitar pedals would you reccomend for metal leads over a hi gain channel?

My current set up is a Peavey Ultra Plus and I play straight through with a wah. I am looking to add effects to my leads, but the effects would have to go over very hi gain. Is there options, is it a delay or echo pedal? What would be best? I appreciate any insight... I have been to three guitar centers and they all seem stumped:)