Mix chili sauce, vinegar, horseradish, garlic and salt in a bowl. Reserve l/2 of the marinade. Add chicken to bowl; turn to coat. Cover; marinate in refrigerator for about 5 minutes.
Preheat grill or broiler. Remove chicken from marinade; discard marinade in bowl. Place chicken on grill or on broiler pan.
Heat remaining reserved marinade in a small saucepan, stirring occasionally. Serve hot alongside chicken.
