SWP gave great advice, try them side by side and see which ones your eyes like better. Best if done near dusk and not in the bright sunshine, that is when you will be able to separate them. I have not compared the Nikons to the Alpens, but I do have a pair of the Monarch 10x42 and like them alot. When I purchased mine I compared the Nikons, with Swaro, Zeiss, and Steiners. There was a noticable difference in the Quality with Zeiss being the best for my eyes. Swaros were a close second with the Nikons third. I decided on the Nikons for the fact I could by almost four pairs for the price of the Swaros. To reitterate my rambling post and point, campare them side by side at dusk if at all possible.
Dakota Kid