Before we go down too far the road of the Helix can do this, or it cannot do that, we should reconsider why we even ride folding bikes in the first place. For me, it was the idea that I could have my cake and eat it too. "Instant" transportation to and from work, or when travelling. It's going to be all about compromises though.
I love my Brompton, but on anything other than asphalt or at least hardpacked gravel/dirt, the bike isn't going anywhere fast. I know there is a lot of concern about the Helix not being super light but frankly to make my Brompton usable with its rear rack and now loaded front bag, etc.... we're topping out at well over 30 pounds anyways. Heck my lunch alone usually weighs 5 lbs once you factor in the thermos and tea and glass microwavable dish! Given that I don't think the Helix can be made *much* lighter on a relative basis to other bikes, I'll pull a Grant Petersen and instead worry about losing a few pounds off of me and what I carry if I'm so concerned about weight when I bike.
As for the practicality of wheeling the Brompton around... meh... sort of. I had to change those awful little black wheels on the rack to roller blade wheels but after doing so, it didn't turn as well if I'm turning around a corner while pulling it. Plus the bike is easy to tip over when things get loaded down. Convenient for carrying and shopping? Absolutely. Perfect solution? Not even close - but it does the job. And mounting and unmounting a loaded Brompton bag is kind of of a pain when you need to fold and unfold the bike. First world problems indeed!
What caught my interest in fact about the whole Helix initiative is that they could squeeze a 24" wheel into a comparable folded frame like the Brompton: hey, I can squeeze more cake onto my plate! I would have paid someone back in the day to build a 20" wheeled Brompton. I would have gladly sacrificed a little bit of compactness and accepted a little more weight for a bike that would go almost everywhere more easily.
Well... we'll see what the first impressions of the early Helix adopters say.