MT prop for RV10

Anyone has experience or advice regarding the MTV-9-B/198-52 three blade prop? I believe this is commonly installed on the rockets.
I know the MTV-9 hub is the heavier, sturdier hub compared with the MTV-12, weighs about 10lb more, has higher Hp rating. The blade diameter is 2 inches more than the MTV-12-B/193-53 (76 vs 78 inches). My primary objective is cruising efficiency and will be installed on RV10.
MT has a 6 month waiting period at present for new props per VANS. The above new prop is available locally.
Appreciate your input.
Johan

prop

The MTV9 is what I am installing on my -10. Main reason is that the MTV12 is rated for 300 HP max and my engine did 297 on the Dyno. You might want to talk to Falconguy, he has the MTV9 on his flying -10...