I tried using thinkorswim in December. It had some additional features but it is mainly targeted towards technical analysis so most of the features are of no use to me. One thing I liked was that there wasn't a limit of 6 L2 screens like there is on Command Center. There was one important feature that was missing from Command Center that prevented me from switching to it on a more permanent basis. I forgot what that feature is.
Ameritrade is in the process of merging thinkorswim with some of their other tools so hopefully that limitation is going away. The new tool that merges thinkorswim with their other tools is supposed to come out soon. I think it is in Q1 of this year but my memory may be wrong. I decided I would reevaluate when the new tool came out.
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