What do you like best about Twinmotion?
Really good, versatile and easy to learn visualization tool, usable both in early, creative stages of design and for final renderings.  I use it on daily basis almost since the beginning of early design phase, in tandem with Sketchup, to see the light-and-shadow play and the context. It is very suitable for this with live update from almost any 3d modeling software and with the perspective from pedestrian POV and via FPP game-like interface WSAD + mouse. 
It allows you to fast test and develop variants and thus make educated decisions during the process. It is very easy to implement into design process thanks to mostly WYSIWYG interface (in opposition to Lumion or Enscape).
There are huge libraries of variety of models included in TM. Except of standard built-in and downloadable  architectural models and materials there are free Quixel Megascans models, textures and decals and free Sketchfab models and also Adobe Substance materials.
For still final renderings I use pathtracing (the best on market in this software segment) and Lumen (for videos) - it is fast and reliable. 
It is very versatile - from architectural design via product design, automotive to previz for movie / entertainment  / advertising industry. 
I'm architect but TM has tools for these industries  incl. specialized materials, tools like LED walls  and scene presets.
TM is based on Unreal Engine (typically the newest available version). There are two main updates yearly introducing bunch of new functions and few small ones between introducing like one or two new tools and or improvements.
Interface is well-thought and easy to learn. It's a solid workhorse which allows you to show what you expected. Supports variety of sources (also via direct link with CAD / BIM /3D modeling software) and which is unique - it also offers export to UE5.
It works on PC and Macs (with native support of M1-M4 chips), on Mac computers it offers Lumen as the best available rendering engine. 
I have good contact with the support. There's also great and supportive community on official FB forum, willing to help and sharing knowledge for free. you should definitely check it as it also presents great results achieved with TM.
Im experienced user and teacher of TM and similar software (Lumion, D5, Vray etc.) so I have updated overview of their possibilities and I still prefer to work in TM.
Full non-restricted, professional version of TM is offered free of charge for businesses which generate below 1 mln USD and for students which is great. Review collected by and hosted on G2.com.
What do you dislike about Twinmotion?
Generally there is only one: Relatively slow pace of development of new functions - but when they arrive they are well-thought. 
You will find more bells and whistles in D5 and Lumion but - to be fair - they often look better on paper than in real life due to implementation problems. 
TM tends to use native Unreal Engine possibilities instead of propriety code and this make the development pace slower (new functions have to be introduced in UE firstly). The upside of this approach is that they offer a long-term live and compatibility.  
Note that TM is GPU based software (hardware rendering) - the stronger is the GPU the faster you will get final rendering. Thus investing in solid GPU is mandatory. Cards from Nvidia RTX 4xxx with minimum 8GB of internal memory are recommended. AMD cards (at least for now -early 2025) should be avoided their raytracing capabilities are poor so they are way slower than Nvidia cards.
For Mac users - lack of pathtracing (only Lumen). To be fair this is caused by poor raytracing capabilities of M chips. The rendering times using PT would be counted in hours (instead of minutes on PCs).
Long time ago (2019-2022) TM had stability issues but these days are long gone, the software is as stabile as it's competitors.
You should check Twinmotion public roadmap webpage to check next planned features. Review collected by and hosted on G2.com.