The difficulty answer this sort of inquiry is that people begin listing cons that are more design choices than anything else.
The reality is that a product manager and design team have to establish a feature list, then design to the list. Sometimes compromises have to be made.
That's also why there are lots of options when one starts looking at xeon tube light sources.
There are, in my view, three classes of xeon flash units; A) speedlites, including both TTL and manual power control; B) Hybrid (my term) for Q Flash, Cheetah, Godox, etc. Bare bulb units; C) studio strobes, including monolights, pack/heads units.
The three classes have overlapping features, power ratings and to some extent size.
So, drawbacks? If one needs capabilities that are predominately in class A or C then its a drawback for a class B device.
I've found that I need all three classes to get done what I need to do. When needing class B capabilities I find the Cheetah is very capable and has features that differentiate it from others. For example, someone above mentions, as a drawback, the proprietary triggers. Those triggers add capabilities not available with generic triggers. Same with Einstein, Profoto, Elinchrom, and others.
So, one person's drawback may be another's benefit. I happen to find the H mode enabled with the proprietary triggers a benefit.
Built in battery is a nice feature. It adds weight to the head, which makes them less useful in many situation. The only two units I know about right now with built in high performance batteries are the new Profoto B1 and the new Godox Ving V850.