I recently upgraded to the Maven B2 9x45s and love them. I'm not a bino expert so I can't intelligently argue the pros/cons of one pair of binos vs. another but I can give you some insight into my decision making process and what my impressions are now that I have used them for archery and rifle season this year. I had narrowed down my choice to either Vortex Razors of the Mavens but I was still up in the air on B1s or B2s. I read everything I could on the internet about the Mavens and was very impressed but I was a little nervious about Maven being such a new company and whether or not they would be around if something happened to the binos. At this point the warranty and longetivity of the company were the only things keeping Vortex in the running. I have several Vortex scopes and love them but I decided to take a chance and go with the Mavens. Now the hard part, B1 or B2 and which magnification. Both had pros and cons like weight, size etc. I was leaning toward the B2s but was nervious about the size. I knew that I did not want the 11x binos because I would be using them in my hands a lot and didn't want to have to deal with them shaking due to the high magnification. After reading a bunch of reviews again I called the guys at Maven to talk through my thought process. Definitely call them if you have any questions. I don't remember which guy I talked to but it was one of the founders. He was on the phone with me for about 20 minutes explaining the different technologies, answering my questions, etc. He said that by far the B2s in 9x45 are their top seller so that's what I went with and I am glad I did. They were awesome during my hunts.
First off the size and weight. They were bigger than binos I have had in the past but no obnoxiously so. after a littel getting used to I love the size and how solid they are. I carried mine in a KUIU bino holder on my chest and did not even notice the weight, so that was a non issue for me even after miles and miles of walking day after day. As I mentioned, I'm not an optics expert but these things were awesome. Super clear and I'm glad I went with the 9x45. They let in a ton of light in at dawn and dusk. I know it isn't possible but it almost seemed that where I was looking was brighter looking through the binos than with my naked eyes. The other guys I was hunting with always wanted to look through my binos when we stopped to glass.
Anyway, I hope this helps with your decision some. I was nervious about picking the "right" pair of binos when I though about shelling out that amount of $$$ but I know I made the right decision for me when I went with the Maven B2 in 9x45. I would highly recommend them.
Edit: I was doing spot and stalk elk hunting in a mixture of open areas, dark timber and aspens in SW Colorado at around 10,000 ft during most of September and mid Oct.
Doug