Ah, GC what a good idea! I have been occasionally trading ESTX but never thought about it from the cost-perspective. IB fees are indeed higher, but total cost per contract above 1000/mth is only â¬0,90 for ESTX. In dollars this is about $1.35, compared to $1,81 in the e-minis, i.e. 25% cheaper. I guess there's also the possibility of IB updating its fees to reflect the current exchange rates. Fees in EUR could be cut by over 25% before they match the USD fees.
The Europe/US correlation is not perfect, but still quite high, so it should not be a big difference between ESTX and ES. Or what do you think? Though it must also be noted that the ESTX contract is a bit smaller, and has higher margin requirements than the ES.
You are absolutely right about the advantages of IB, too.