Sounds like a Center Pin connection Issue to me but I am not familiar with the Herakles....
Got the X Cube. Loaded the Erl K Ti built to @ 0.21 ohm and downloaded the Ti Profile.
Lethargic.... Remembering the Vape Chronicles Vid (embedded previously) and the Reviewer saying he found it weak as well, I also remembered his Theory on Why and his Solution. So, went into the settings and adjusted the TCR from the Ti Default of .00350 upward to .00440 and hit it again. Thar She Vapes!
He had theorized that the Smok TC Algorithm implementation is incorrect and/or the TCR "low" (purposeful or not?) and that raising it around 1 thousandth makes it come in and fire just right. I would co-sign that Theory after having proved it again in my Case.
Anyways, set at 470-480* F on Ti Single Coil (EK is a Single) Normal Settings the X Cube II does an Awesome job and yields a great and highly pleasing Vape. Hearty & Warm. Steady and Predictable. The TC Software performs as advertised and expected. Still new to it so little soon to tell but, I'd say I really like this Mod and will for a long time.
The X Cube II itself is amazing and so User Customizable I will agree that that this is the new Benchmark as far as that and Bells & Whistles go. Not just useless Snazz and window-dressing. It is highly functional and does add greatly to the User experience. If you are a Tech and Gadget Person, ya gonna absolutely love it. The Weight is good (if you prefer Substance and not a Minmalist) and the Design Layout is pleasing both Aesthetically and Functionally. At this point, I completely disagree with those who moan about the Battery Door and the Magnets thereof. Zero Issues or Complaints from me. Buttons are just right (not flimsy, rattily, or stiff either) and after you get used to the long Plate Firing Switch it is nice and pleasing as well. None of the screws on this Device needed to be tweaked or adjusted at all right out of the Box.
Display is great, easy to read, centered, and the ability to "Flip" it depending on how the individual prefers to hold it and vape is nice. Thought would prefer it better is auto-rotated like the SXMM but after using it,,, naw. I like it to stay where I put it. The Top Mount Screen is sweet. Like to be able to see the Screen while I vape just be looking down as I thought I would. HUGE Plus in my book.
Device is Solid and well-built. Finish is well-done and if ya like Stainless, you will dig this metallic Beast. However, the Beast IS a finger-print monster as well. I have a textured black Snake-Skin J-Wrap on the way and believe that will fix that Issue as well as add (IMO) much needed Grip. Not a Fan of "slick" (grasp-wise) Mods but I do love the Stainless look. Needs some Black on it anyways. Only thing prettier than Black & Stainless is Black & Chrome

I do plan to do a couple custom Cut-Outs on the Wrap so that the X Cube II Logo and the Smok Logo still show. Leave the Top and Bottom Plates unwrapped and this Beast should dress-up real nicely.
Mine came already pre-loaded with Firmware Version 1.08 so no experience or comment on the Download/Upgrade USB Data Cable Deal.
The In App Ti Profile download and install went by the numbers with no problems at all.
The App is a little "glitchy" at times on the newest Android Firmware but that seems to be somewhat common by the Posts on the App included Blog Site.
Biggest glitch is it doesn't recognize the Mod and won't connect at times. Think may have figured out the Solution when it does that but not proven enough times yet to say definitively. Otherwise, really dig the App and how it controls and integrates with the Device. Definitely of value and will be utilized as much if not more than the Mod itself to change Settings and Features.
Overall,,, I give it

without hesitation and as long as it doesn't fade or become twitchy or Schizo on me it is definitely a Keeper. Wonlt be selling it off when the next Biggest-Best-Greatest comes along.
If the sound and the Vids of this Mod Flip your Switch-Buy It. You won't be sorry or disappointed.
Thanks to dcfluegel & The Vape Chronicles for turning me on to this new Bad-Boy of the Ft. Vape Armory Arsenal

The Hollowpoint Mech is torqued though,,, It stayed at Base HQ today instead of being on Point for daily Work Manuevers for the first time ever.