Its not the case of taking the machine up stairs. I have never taken any machine up stairs. Machine always sits outside customers door. Rain our shine, machine works, we put a cover over it. Most properties have some form of canopy anyway. When your doing 3=5 jobs a day, 5 days a week, machine in and out (unless you want a truck mount, or have it fitted as a tm) then its pain (well for me it is) . Internal heater not fussed for, just adds more weight. All you need is a magma or a v2 (separate in my case) and you have instant heat.
Just been able to clean inside the dump tank is great with the new Miniflex won it for me too! Power behind the Miniflex HX is awesome. Carpets are not far off being dry by the time you pack up.
In this industry every machine has its pros and cons, each can be tailored to each operator and what he/she wants from their machine and best suits your needs. Some might prefer the big enforcer or storm, others smaller just as powerful machine (as the bigger models) due to weight. Either-way, happy cleaning!
You can see my review of the machine. Had it around a month now.
https://youtu.be/uLGQ1_C6rqM