Place tenderloin in a large heavy-duty zip-top plastic bag.
Combine hot sauce and next 3 ingredients.
Pour over tenderloin.
Seal bag; marinate in refrigerator 1½ hours, turning occasionally.
Remove tenderloin from marinade, discarding marinade.
Prepare a hot fire by piling charcoal on 1 side of grill, leaving other side empty.
Coat food rack with cooking spray; place rack on grill.
Place tenderloin on rack over unlit side.
Grill, covered with grill lid, 30 to 40 minutes or until meat thermometer inserted into thickest part of tenderloin registers 145° (medium-rare) or 160° (medium).
Let stand at least 10 minutes before slicing.
Serve on buns with Mustard-Horseradish Cream and, if desired, arugula.