I've seen a lot of commentary in the forum regarding low end porros being superior to low end roof prisms. I would not argue this statement as porros usually seem to give a good view to my eye as well. However, that being said I have discussed with two of the more reputable binocular dealers in this area the notion that buying a $300 range roof prism is a waste of money. Both dealers who regularly test new and old models of all kinds have expressed to me that manufacturers have become more advanced in the design of roof prisms including the kind of coatings on the lenses. They said that you can get a very good quality roof prism binocular in the $300 range where as that may not have been the case 5 or 10 years ago. They were also of the opinion that if you were going to make the jump to a higher quality that you might as well go for the top of the line and skip the mid range. In other words invest $300 or $1500 but why bother with the in between. These are not the end all of opinions of course but just another perspective. One dealer mentioned brunton and swift as having good quality low end roof prisms just to name two.
I agree with these dealers. In cheap roofs, I'd get a Bausch&Lomb/Bushnell 7x42 Discoverer for $300 (until recently, this was easy, but it may not be possible anymore due to price hikes). Failing that, I'd search around to find a used/refurbished Swarovski 7x42 SLC, Zeiss 7x42 Classic, Leica 7 or 8x42 Ultra/Trinovid, or Nikon 8x42 LX for around $500, or maybe a Bausch & Lomb Elite 8x42 or Nikon 8x32 LX for $400. Otherwise, I'd give up on the roofs and go for a nice new Nikon 8x30 EII for $240.
--AP
For brand new current model bins I totally agree with the $300 or $1500 sentiment (more like $250 or $1,200 for what I prefer). However there are some new inbetweeners that I haven't heard much about yet, the new Stokes models and the Leupold Gold Rings. Otherwise, at the in between prices I would consider used premium models or discounted older lines like the Nikon HG/LX. If I had the money to throw around I would pick up a few pair of the 8x32 and 10x32 HGs.
At $250-$300 I would look at the Bushnell Legends, Celestron Nobles and Nikon Monarchs.
I don't care how great optically any porro is, due to ergonomic considerations I don't think I will ever use one as a main birding bin ever again.