Are those cheap 15A receptacles rated to be wired up as a pass-through for a 20A receptacle circuit? EG, put the wire in from panel on one screw, and out to the next rcpt on the other screw? There isn't any labeling on them to indicate that the jumper bar is rated for 20A, but I've seen this done before.
Thanks guys, that makes it easy I only have 1 multiwire string in the whole house (two 240V 30A tool outlets in the shop) and was planning to pigtail it regardless!