Mastercoat is much better than Banana Republic, without a doubt.
It's one of those made in Italy brands that nobody in the US has ever heard of but that makes pretty good stuff and can often be obtained for next to nothing on yoox or ebay. I have a few items from them, one of which is a cotton blazer with working buttons on the cuffs and a really nice fit (retail was about $800 and I think I paid $40 or so). The brand isn't Kiton or anything, but it's pretty good. Same goes for Orlando; I have several pair of jeans I picked up on yoox for about $30 that are great. At full retail, I believe both brands are quite pricey, but again, they go for nothing on yoox or ebay because nobody outside of Europe (or Japan) has heard of them.
Overall, keep in mind that pricing or obscurity of a brand on yoox really has nothing to do with the quality or fit. Yoox prices its goods at what it thinks people will pay; some brands come onto the site at 70% off retail, other brands (Dior, for example) often come on at nearly regular price and usually sell out. So, a retail $300 pair of Dior Jeans might come onto yoox priced at $290, whereas a $1500 Ma. Co suit might also get listed at $290 (I got a fully canvassed one in Zegna Mohair fabric for about that a few years back).
So, just because it's cheap doesn't mean it's not good. There are several threads around here talking about our favorite brands nobody has ever heard of, and Mastercoat and Orlando are often mentioned. Lardini, Ma. Co, Tombolini, Tonello, Asola, Phtalo (sp?), Post Card, Piombo, etc. are some others that sometimes make neat items at very cheap prices on yoox and ebay.