If you run a search on the word Swift, you will see that we have mentioned these scopes frequently. They are in my opinion one of the absolute finest pieces of glass you can buy for the MONEY. I have several and have never had a problem.
I have compared them side by side with lots of other brands and they hold their own quite well. I have had and recommend the 656 and the 674 Premier. You will be impressed with these models as many are.