Since Benchmade has never worked with S90V or Elmax I don't have much hope it ending up in a knife, at least not any time soon. M390 seems to work really good for me and I believe should have better edge holding than Elmax. Heck, I wouldn't even mind D2 since their heat treat of it seems to hold an edge better than most other steels they use.
I really hope yall go with the Rift. Tan G10 is Ok and can probably be dyed many different colors for those that like to mod their knives and should turn a nice jet black for those that like a regular black knife. I'm not sure I would buy the 940 as I'm just not a fan of the long skinny blades and I'm definitely not a fan of aluminum handles. I might buy one if it ended up with some G10 scales instead of the aluminum but I would much rather have the Rift and like I said before I would probably buy at least 3 of them if they aren't priced at MAPP pricing and are lower and more in line with old Benchmade prices and other companies pricing.