I was leaning towards the Boston myself actually, so that will be the one I try and get I think. Soundstream will be next if the Boston is not available. Warranty is a risk on these purchases for sure, a bit like buying second hand, but most warranties are only 1 year anyway. In my case shipping cost back to the manufacturer would cost more than paying for any repair myself, so I would just do that. Buying a quality product should mean that I have no problems though, so it is a small risk I think.
The size would be a problem for a lot of people for sure - these suckers are big. In my case though it will not be a problem. I am converting 4x4 wagon into a dual cab, so when I make the new rear firewall I will design the audio into the build. Amps, subs (two 8's), crossovers, and a set of the 6.5 Focals will all go in here. It is good to have a lot of space to do this stuff, sure makes it easier.