I am evaluating technologies for building an e-commerce store. In the past I have created both Razor and SPA sites (using Angular) but none of them have requirements like an online store where fast response and security are key.

Right now I am leaning towards SPA using Angular because of client side processing resulting in , barring any mistakes or bad design, a quick response time. I am more worried about the security aspect and want to know if anyone here can suggest something.

The user on my site should be able to order items in guest mode i.e. without signing up for an account. With this in mind how can I ensure that the cart or any other transaction data is not compromised. I will validate the data for each server request but will it make the things slow if I create a SPA?

With Razor I think this kind of logic will work faster with all the data attributes, session maintenance and such.

Any thoughts?