Back 'in the day' my 1st MOD's were tube like. In those days they were VV (Variable Voltage) regulated, 1-3 buttons and generally took 1-2 18350's as the replaceable battery(s).
As time moved on and devices evolved I generally went onto using other shaped mods. However I always liked the 'tube' form factor. Fast forward sometime later Dicodes was offering (at the time) the only Temperature Regulated Tube mod on the market. However costing $200-400 a copy (depending on model) they were rather rare and could generally only be ordered from England as an import to the USA.
At some point in time Ehpro released their '101' mod for <$75 which they claimed could also do TC mode. Frankly I'm not sure how much I paid for ether the Ehpro or the Dicodes (I own 2 of them, one SS and one Titanium version).
Mounted on the Dicodes25 is a KF5-25, on the Eh101 is a KF5 clone. Funny, they both perform similar and have similar functions.
While the Dicodes might still be in production, the KF5's and the Eh tube mods are no longer in production
So what's the point? One of the setups cost over $450USD new while the other cost ~$75 new.
Moral of story: Cost does not always equate to anything more than cost.