[Discourse.ros.org] [TurtleBot] [TB3] Very informative and detailed review by Erico Guizzo and Evan Ackerman
I've found a couple of reviews about TurtleBot3 that might give you an idea of what the TurtleBot3.
I find these articles are amazingly informative when it comes down to get ready to spend some money.
You will find bunch of pros and cons about TurtleBot3 based on objective investigation.
Take a few minute breaks while reading them :)