I am looking to replace some windows in my home. The contractor bidding the job is trying to sell me the Andersen 200 series windows. I did a little research and found the Andersen 400 series windows were of better quality and not that much more expensive than the 200 series ($100-$200 more each). The contractor just told me that he cannot get the Andersen 400 series windows in the correct size to match my rough openning (44X39). He says the closest rough openning they have is 37 5/8 X 44 5/8. I find this hard to believe. Is this true? Thanks.