I have purchased an hour ago.
Nusii has a good looking interface, it's intuitive and options are OK for a start, but most of it can be implemented with a WordPress. You have to add many more options to make customers want to use it.

Here are some of mine observations:
- In dashboard in Country drop down list, countries are not sorted alphabetically. Serbia among countries starting with R. This is probably because somewhere you've entered "Republic of Serbia".
- In "Custom domain" you should add a full example of what you expect us to do. I often work with hosting and DNS I am still not 100% sure what needs to be done. An example like this (proposals IN CNAME seoenergy.nusii.com) would help. In short, I would list a few examples how this should look like on the same page, not on a help page.
- If I send an offer with 3 packages available, I'd like to have option to let customer check only one. So it would be good to have option to set addon services (here customers can choose as many as they want) and packages (here they can choose only one)
- On offer bottom, bellow Total, I'd like customer to see in short what options he has checked, not only the final number. Is this possible?
- Can you add the option for customer to fill out a custom form after he clicks accept proposal? For example for SEO services: site name, user, password, keywords, competitors, special requirements and similar.
- Can we set a custom email to be delivered to the Customer after he accepts the offer?
- I haven't seen option of payment integration.
- Can you please integrate payment via Payoneer.com (about 10m users world wide)? Payoneer is extremely popular with freelancers on Fiverr, Upwork, Freelancer and similar freelancing platforms, especially for users outside of US.

That's all for now.
Wish you all the best.