I've had this discussion with the Admin(s). Inserts are to be listed with the sets that they were issued with. In order to make it clearer, Topps inserts released with OPC sets are identified as "Topps ...". For info on which inserts were issued with which product, take a look at the checklists or packaging (wrappers). Do NOT rely on "what Beckett says". For a few years during the early 2000's, many inserts sets were released in both Topps and OPC without distinction. In fact, this has occurred in the past as well, (e.g., 1969-70 Stamps, 1970-71 Topps Stickers). They were issued in both Topps and Series 1 OPC (look at the wrapper).
~Rob~
Hockey set collector including inserts, ERR, COR, VAR. Knowledgeable about 1968-69 to 1994-95 hockey.
All 1990 and newer cards for trade are NRMT. Expect the same in return. 1989 and older are assigned a grade. Everything on my trade list is available for sale. Reasonable prices based on condition. If it's not on my tradelist, it's not available.