Ensign works well with IB. You get free historical data from DTN. Ensign will connect automatically even with front end software already running. It is $40/month. Never had an issue.
I will look at Sierra and Ensign next week. jTWS Dump looks interesting too - cost is 79 Euro.
whitster, it's good that you pointed out that IB data is not true tick. I was aware of that (and didn't they recently tweak the number of ms between aggregations?).
Does TradeStation provide you with the bid/ask data you mentioned?
Correct ... IB will send a packet every 100-250ms (not sure what the minimums are) but it still provides "effective" tick data if not tick by tick data.