I cannot provide the answer you are most likely seeking but . . . I've come to the conclusion that the iPad may not be the most approriate mobile device for every mobile situation.
Apple's MacBook Air is now a competitor in terms of cost, size, weight, performance and peripheral interfacing for those situations where the iOS has not yet evolved to allow the most appropriate interface tools for human interaction, or a simple way of connecting inexpensive peripherals.
I've discovered this with a barcoding scenario and your type ahead issue might be another.
I am assuming you are referring to using a portal to bring up matches of say a last name to go to a detail record.
I used the six fried rice incarnation of type ahead on my very first iPhone FMGo project almost two years ago. It's still working.
You can also use a script trigger (on modify, so it works as the user types) to perform a find to display results in list view. This works with Go as well.
Thanks for the ideas. I will file this away for future look at. A second look at my use case shows that I don't need a type ahead at this time.