Laser 3d In My Backyard ?
From what I know, the Laser 3D (Electric) is going to need a fairly good sized back yard. I fly a Champion (from Hobby Lobby) which is basically the same type of plane (though lighter) and it would require a fairly good sized yard.
You mention it has half the wing loading, well just because of that, it doesn't always fly at half the speed. Example: A small small .40 size glow plane with a 30 oz p. sq. ft wing loading is going to be a hot lander, where as a giant scale warbird will be very happy to have a wing loading of that.
I think the 3D has a thicker wing than my Champ, which will mean slower speeds, but the 3D is also about 3 oz more at the stock weight than my Champ.
The Stock Champ weighs 10.5 oz mine weighs 13.1, 13.1 is a really a really light setup for the 3d, I've heard that they are running more like 15 oz rtf.
Just because of that doesn't mean it will be hard to fly in confined spaces. Its all about skill level. If you fly the .40 size version decently, the small one should be no problem. I can fly a .40 size fun fly in an area that some people wouldn't be comfortable flying a parkflyer.
Bottom line, if you can handle your big one no problem you shouldn't have any problems with the little one. I would test it at a bigger field before you go flying it in your yard so you can get a feel for it.
Sorry to be so long winded
--Paul