Is FormTitan a SurveyMonkey alternative for Salesforce forms?

Yes - it is.
SurveyMonkey is a popular online tool for creating professional surveys. The fact that it focuses on surveys gives it an advantage over other tools in this field. However, this advantage can also become a disadvantage if the user wishes to create other types of forms as well. It's a good tool but has its shortcomings like: it's limited in editing styles of elements, has no option to insert Html.
FormTitan, in comparison, is a robust platform for creating any type of online form - including surveys. It is built like a "Lego" allowing you to mix and match the features to create your own custom form. This means that you can create a survey that is dynamic, one that uses conditional logic to show/hide questions based on filler responses.
As for the Salesforce integration: Surveymonkey offers a one way integration with which you can write data in Salesforce. FormTitan, on the other hand, has a powerful 2 way integration, allowing you to both write to Salesforce and Read from Salesforce.