I like to buy 4# bags of IQF chicken legs. I cook the whole bag at one time, as my kids go nuts for them. Usually, I fry them in my deep-fryer. Sometimes, I'll grill them.
I've never had an issue with chicken being "stringy". Yes, there usually are two small pieces of tendon, but I just pick those out.
Turkey legs are a whole different story. Those are best smoked. I've found that the tendons actually make great handles to dip the attached meat into some BBQ sauce