I got 16x42 with MP-8 and I love it.
I did a comparation side by side with Leupold VX III 6-20x50 with 30mm tube and I setup the leupold at 16x power to be the same as IOR.
I ranged far far away with both scopes and IOR bit by far the leupold (sorry leupold guys) by CLARRITY, CRISP IMAGE AND BIGGER FIELD OF VIEW.
Yes field of view bigger then Leupold and the IOR is 16x42 with 30mm tube.
I could not belive my eyes the quality of this scopes.
To answer your questions, go with 16x42 and get from Gene at optic buster the 3x lens adaptor.
Here is his review:
I am not familiar with the IOR scopes but if the eyepiece is between 1.4 and 1.75 inches in diameter, we have a polymer rubber adaptor that will slip on the scope and it should work fine. The 3X one will enlarge the image to abot 20X. The lens is $100 and the adaptor is $5. If you want to try one know it can be returned for a full refund, send a check to:
3450 Pleasantville Rd. NE
Pleasantville, OH 43148
So this can ansver your questions and also get you more power for pdogs at 1k.