I am considering using thinkorswim as my backup broker. I searched the site but the references are to options spreads. Does thinkorswim support spread futures orders (as a single order)? If so, will it only leg-in, or does it also support exchange-native spreads? I am interested in calendar spreads in CL, NG, and Soybeans (where I want to see and trade the exchange native spread price as a single order); and inter-commodity spreads such as ES versus YM (where legging in is OK). (In summary, I am looking for IB's Combo feature for futures). I will appreciate information, insights, pointers. Thanks.