They also offers a free landing page which I could customize. I wanted to ask you - do you think that it is good idea ? Do you know any other sites like this?
Hi Sara and welcome to the Sitepoint Community. The landing page they offer might not suit the startup as it looks very specific in terms of design but put it this way, will you learn anything from using it? If you answered yes then download it, if not try and create your own from scratch with ideas from the template and other landing pages around the web.
I suppose it comes down to whether you actually want to learn from it and if you have the time to invest.