I bought a new Dan Wesson .45 bobtail commander last year (see my past posts on it if you wish) after doing a lot of research, both practical and otherwise.
The DW is over the top in terms of quality, performance and fit and finish. I can truly say it is a high end gun for mid range money. I bought it from CGN sponsor ArmsEast where Walter took excellent care of me and a friend of mine who also bought one at the same time.
As for the weight issue, I prefer a non-lightweight frame because the lightweights seem unbalanced to me, with a relatively heavy slide balancing up on a light frame. When shot, the lightweight bucks more and is not as nice to shoot, nor as accurate.
So if you live in Canada, you're not allowed to actually carry the gun anyway, so weight savings are not worth it, IMHO. I do urge you, if you haven't already done so, to actually try shooting commanders of both regular and light weight configurations before you buy anything, else you make a commitment to something you will end up not liking to actually shoot (which is what two friends of mine did with Colt lightweight .45 commanders).
Practically speaking, I find the weight difference not worth it, and not that much to begin with (but then again I am a big guy, so it's a personal issue of preference). As well, the bobtail design is excellent, and fits my hand like a glove - again, if you haven't done so, compare this for yourself too.
Good luck and I hope you make a well informed choice that you will be happy with!