I decided to save myself a couple hundred dollars and talked myself out of buying one of the new LV 5 1/2 jacks. I already have their smoothers, and they are nice, but heavy.
Instead I used those "savings" on old ebay Crafstman No.6 and got No. 8 from here (still waiting on it).
Just got the Craftsman made by Miller's Falls and it is nice and light, 6 lbs and 6 oz or about 2.9 kg. 3 oz. lighter that LV 5 1/2 jack and whopping 22 oz lighter than Woodriver no. 6.
I ended up weighing some of my planes and my old No. 5 jacks are about same weight as new No. 4 smoothers. I actually like a feel of old lighter planes better and I am a decent size and fit guy at 6'6" so actual plane weight is not really a concern, but the feel is.
I wonder why all modern manufacturer's are compelled to use heavier weight as a positive feature. Do people really prefer heavier planes or is it easier to manufacture these heavy planes? New LV custom planes actually are lighter than the their old planes which actually persuaded me to buy their new smoother to try it out. They could go a step further and actually sell a plane with an adjustable "balast" feature I used to have a gaming PC mouse where you could adjust it's weight by inserting these metal pieces in special cartridge.