Congratulations on your new additions!
I would encourage you to take another look at a Martin's cage before making your final decision. When they are powder coated, I believe they are much nicer looking than the rat manor. They are definitely more durable and well constructed and, more importantly, they have larger doors than the rat manor, making it much easier to clean and to accessorize and to handle rats inside it. Since you are looking for easy to clean, you should think twice, because the rat manor is not one of the easier cages to maintain, and its construction is much more flimsy than a Martins. I honestly believe that you will be much happier long term with the Martin's cage and, while it may be pricier than a rat manor, it will last you much longer, making it worth the extra money. Martins cages also tend to have decent resale value, so if you decide you don't want to stick with rats after these, then you will likely be able to get some of your investment back selling the cage used. Also, the fact that it has a larger footprint is a big plus to me as it gives the rats more running room - especially appreciated by females who tend to be more active.
I only say this because when people opt for less expensive options with regard to the rat cage, they usually end up regretting that decision fairly quickly and end up buying a better cage in short order either because they one they started with didn't hold up or because they got sick of dealing with it. They end up wasting more money by trying to save money.
That said, if the rat manor is really the cage that you love, it is the one pet store cage that can make an acceptable home for a pair of rats, so if you are firmly sold on it, there is nothing wrong with going that route and I am sure your girls will be very happy.
Good luck with your girls. Keep an eye on the one that is sneezing. Sneezing is not unusual in new rats as they adjust to the new environment. However, if the sneezing doesn't improve in a week or two or if other symptoms develop, you may want to get her checked out just in case.