After returning two pairs of dragons, I went for the solutions. I did not originally want these shoes because they look strange. However, their performance speaks more than looks. I wear a size 10.5 street shoe and ordered these in 40.5 (M's8) and ended up downsizing to a 40 (7.5). I wear 41's for testarossas, which I consider a bit too large. I hear a lot of reviews about how comfortable these shoes are. True, they are comfortable for how tight they run, but I think that one person could easily size into 3 different sizes of solutions and claim they feel snug and therefore fit for climbing. When I received my first pair (40.5), I struggled to get them on because of the lining. It is so tight at first but not in the toe, just the width. In my opinion this pair was far too small to get the delicate touch needed to snag tiny holds bouldering hard stuff. I am very happy with the size smaller (40). I will say, I could barely get into these shoes, it took a solid five minutes to get my feet into them, but each time after that it has become easier to get into them. They aren't as comfortable as they were before, but I am glad I downsized. Note that this is is nearly 3 full sizes down from my street shoe, and I can stay in them for a good 15- 20 minutes comfortably.
Conclusion: The reason you see people using solutions for everything from trad to bouldering is because you can size them differently for different purposes. If you want to die hard aggro toe that will put that XS grip to work on tiny stuff, stuff your feet in them. If you want something more comfortable for gym climbing or longer stuff, get the comfy ones.