What do you like best?
First of all, to use Matecat you only need to upload a document to the website and choose the source and target languages; once this is done, Matecat provides you with two general choices, either you work with the automatic translation for free or submit your document for paid professional translation. I've only used the automatic translation, I haven't paid anything and I've been able to work on the website using an internet connection, downloading the final draft (corrected by me), or downloading a preview and working without an internet connection.
As for the automatic translation, even though it generally presents grammar mistakes or too literal translation, Matecat provides you with three options with different levels of accuracy to translate separate sentences, paragraphs and even phrases; but if you don't like either or can think of a better way to translate them, you can write your own translation.
You can translate specific chunks of the text (separated by Matecat based on punctuation marks) instead of seeing the whole text on the screen all the time, which, I believe is fantastic because it keeps you focused on that particular paragraph, sentence or phrase.
The website is user friendly, it's organized; if you work directly on it, it keeps the format of the original text untouched (fonts, margins, style...), shows spelling mistakes and provides you with help to be able to translate without problems. And, a bonus, if your internet connection goes down, your work will be saved (only for you to see it) on the website, so you can come back later and keep working.
What do you dislike?
Since Matecat is a Computer Assisted Translation tool, in several cases, the translations provided are not quite accurate, based on the target language, or even have grammar mistakes. This means that, in order to have a good experience using this CAT tool, the person must have advanced knowledge of both the source and the target languages. Also, you must pay full attention to each phrase, sentence or paragraph you are translating so that you don't miss any mistake or a too-literal translation, which, even though it could be grammatically correct, it would not make much sense in the target language.
If, by any means, the source language has punctuation mistakes, the chunks of text Matecat separates can break the original ideas and thus, create problems in the final translation.
Finally, if you don't want to work on the website and you download the preview (without correcting it on Matecat first), it's highly probable that you'll end up with a less accurate translation (more work to do), with format problems, and in some cases, with untranslated sentences or paragraphs .
Recommendations to others considering the product
Matecat won't translate anything perfectly for you, you need to work, know both languages you're using and focus on getting the translation done properly, but it will definitely help you work faster.
Anyone who knows at least two languages can work as a general freelance translator as a main or extra source of income; using this website would make it easier for you.
Any document you upload to the website will be kept private and your progress will be saved until you go back. You won't need to worry much about fonts, style, margins, among others; only on correcting the automatic translation so that you can deliver a more accurate one. All of this for free.
Also, if you are not really interested on translating a document yourself, you can submit it and pay for a professional translator to do it for you.
What business problems are you solving with the product? What benefits have you realized?
Currently, my main source of income is being a Freelance Translator, since working as a Teacher (my Profession) in my country didn't result as expected.
Matecat allows me to translate faster and that means I get to earn money faster. Nevertheless, it still requires advanced level of both the Source and the Target Languages so the job gets done correctly; but, as part of it is being done by this Computer Assisted Translation tool, I can work with it and correct it, instead of starting from scratch.
I've also increased my vocabulary having the text as context without the need to check on a dictionary; this translates into being more proficient and able to know about several topics, which can mean bigger opportunities for me as both a Freelance Translator and an English Teacher.