I think you should try the "Big Twist" (BS mains/MT crosses) first. As
@Spoon suggests, string the crosses 4-6# lower than your mains.
If you try TH/MT, I'd be interested in your review. It seems to me the rifling grooves of Magic Twist and the edges of Tour Hex might impede 'snap-back' or have a higher level of friction than using a smooth cross.
For me, the big difference between Big Twist and FireWire Boost is predictability and power. FireWire offers more power, IMHO. Whereas BT excels in predictable response because of its twisted profile. String the two side by side and you'll see nearly all the apexes on the Big Spin string bed are facing up on the string bed at every string intersection. With FireWire it happens but it is inconsistent across the string bed. Mayami seemed to have nailed the perfect rotation value. I would think if the twist were more or less frequent the inconsistent direction of the apexes would affect the response.
What you may want to try is Big Spin mains with Ghost Wire crosses, which is on my list also to try out once I get out of the current multi/gut mains - poly cross phase I'm stuck in at the moment ... LOL. Without even trying it, my expectation is the combo would have Big Twist responsiveness with a little more pop and a softer feel on impact, depending on which GW gauge you install.
Another hybrid I'm diggin' is Big Spin and Toroline's Wasabi (pink). This combo was like Big Twist but with a super crisp feel/response.