Here is what I can tell you, there was a review by a couple engineer types here in a thread or 2 about it. I have looked at some differences and one being the tube weight which was heavier on that hf model. I am having a puter glitch and my faves are scattered. Link them from HF here in this thread. While both models may be great I can tell you for a fact the one is about as close to perfect as it can get and the price is a bonus.
I am a welder and wouldn't even consider building one, the thing was so good, fit, finish, paint. I remember when my bud Rick got it, he bought a 5 T long reach jack at the same time, we were real impressed you can get it that good at that cost. The cherry picker has sufficed but like most small places remains parked most of the time. (a good thing to remember here is generally you will rarely use this) The jack was used hard.
An engineer here reviewed the boom design, was plain as day they let the new kid with the slide rule loose. As I recall it was on a 1 ton model though?
He used the HF unit in comparison with draw over the flaws explanation and I can personally vouch for the tube weight differences in some and for its actual use.