Excellent Salesforce Integration and A+ customer support.
Form titan provides a very quick way to integrate with your Salesforce instance. There is a lot of flexibility provided and the support team is one of the best I have seen. Once you get this tool, spend just a little time with support and you will be up and running in no time.
The best part about Form titan is that they are always working on improving the product. If you think you are missing a feature, mention it to them and check back in a few weeks and it might just be there. For example, they just added inline edit for tables and related lookups (4 deep) - I am very excited about that.
If you are looking for a form builder they have a free trial - give it a try.