I've been thinking about using an A-Wing test pilot with Determination and DTF as a cheap and agile Crit sponge for low agility Falcon / B-Wing builds.

Correct me if I'm wrong but the wording on DTF seems to indicate that I must elect to pass the uncancelled critical before the face up damage card is revealed (assuming it's not just going against shields). So I can't wait to see what the crit is before deciding whether to pass it.

Is that right?

Yes, you're right you can't wait.

DTF lets you take the uncanceled <crit> result and transfer it to another ship. You don't deal cards until after all dice modifications have been done. So by the time you flip up the card you're past the point that you can transfer the <crit> result.

Results -> Damage -> Cards.

Draw Their Fire works on Results, which are processed well before you ever get to cards.

Thanks guys - I thought as much but I can see this being misplayed quite easily

It's a very common question

It would be a good combo on something like Chewie who could take the [kaboom] results regardless what they are and then either discard them due to Determination or "fix" them with his pilot ability. On an A-Wing, where it could actually be done, the risk is just too great as most of the time you'd just be pulling a [kaboom] to your frail little fighter.