Every level II service differs a bit from one another but they basically provide the same info. From an aesthetic point of view you may like one over another. I don't use either service so if someone reading this does, please chime in. My concern would be if their service works properly all the time and if their feeds provide valid quotes.
I use both at the moment. I have been purposely watching to see if there were any differences and have found very little. I am in the process of switching my accounts to think or swim and doing away with the service with ihub simply because of the duplicity and no need for the extra expense since the level 2 is free with TOS. Good luck and Happy Trading.
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