If the cost is no problem for you, grab up a pair of 10x32 or 10x42 and enjoy. Nothing odd about having both an 8x and a 10x. Perhaps a pair of Meopta MeoPro 10x42, or if the budget allows, Conquest HD? Try not to go cheap. You can get some very good glass between $500-1000.I live in Southern California about 30 min from the beach (Seal Beach National Wildlife & Bird Sanctuary) and 45 min from the San Gabriel Mountains. I have not yet gone to either yet but plan to. I have been doing the backyard thing and have gone to a few parks and local arboretums. I like my 8x32 Vortex Diamondbacks and they have been fantastic but was thinking of adding a 10x so I could get a little more detail for the further out birds. Does this help as to one of the reasons I was looking into 10X
The extra reach with 10x, compared to 8x, is noticeable. I think at the beach sanctuary, especially, you'll appreciate the extra magnification with 10x.