I've never seen a Hadco well light like that before....it looks more like something that OLP uses...either PM or B&B....unless it's an old Hadco? Anyway...I think people have their own ways of design. Nothing bugs me more than seeing a home lit up with all MR16's...or even all PAR's for that matter. It shows a complete lack in design skills in my opinion, or they just wanted to get the job and get out without spending much thought on it. Again..to each their own...as long as the customer is happy.
I'm definately the minority here. I don't like using MR's on the facade of the home (unless down lighting of course). A lot of it will depend on window placement however, the height and pitch of the peaks, the grading going up to the home, and whether the home is sided, stucco, or brick...plus many other factors. The same can go with trees...what kind of tree, what size is the tree, what you are trying to emphasize on the tree..etc. I don't think there is a good solid answer to which fixture/bulb is better just because it can be easily said that each bulb has it's place.