UX research companies are your best bet for creating personae. They understand a lot about your users from you and your team, then go on the field and talk to a certain number of users (online or face-to-face), they will finally create rich personae for you.

If you want to conduct conceptual testing of your product or service, UX research companies will help you find right people and run formative or validation research.

What does a card really do?
- It helps clearly group information
- It helps group information with relevant tasks
- It can help to show quantity of information according to need
- It can help show other aspects of information normally not seen upfront

There are several ways to group information as per the need of the users and brand. Graphic designers and user experience designers have been grouping information as a part of their job.

In the recent times, a lot of people needed to group and categorise information. However, without the knowledge of Gestalt's Laws and training in graphic design, it is a guessing game for anyone. At that time, card based UIs came to rescue - they did the job perfectly - and looked good too!

So, if you and your designers have zero training in graphic design, and you have an information heavy website/application, card based UIs can be good.

And, one word of caution, group information that makes sense to users together (even if it comes from different database tables). Do not naturally group information that are columns in the same table in the database!

My company works with user research recruiters regularly. Here are some insights about agencies before you go ahead and employ one:

1. How may user research recruitments have they done earlier. The more experienced they are, the more they understand that user research recruitments are done on psychographics and not on demographics alone (as in Market Research). If the agency is not experienced, you would have to work a lot to get them to deliver acceptable quality of recruitments.

2. User recruitment agencies can be found across the globe. While working with them in different countries, we have found out that agencies from high trust countries (like Singapore) usually found far better participants with negligible screening. However, in low trust countries (like India), agencies will provide participants of 'passable' quality with a lot screening time at your end.

It can be safely assumed that people from different cultures will behave differently with the same product. They have different aspirations, motivations, circumstances in which they use a product, use cases, and social meanings.

If you are launching the product in countries that are very different culturally, it makes sense to conduct usability testing in different countries.

Usabilitytesting.com recruits users from a pre-selected panel of users who have given consent to be a part of usability tests in general. When you test with these set of users, what you hope to catch are low-lying usability fruits like fonts, colors, labels, widgets, etc.

Key issues like navigation and intended behaviour nuances will not get addressed as the users are not 'intrinsically motivated' to complete the tasks. The users are neither motivated to apply for a Certificate of Deposit online nor interested in buying a pair of hiking shoes online for the upcoming K2 climb.

Usabilitytesing.com is great for things which most people regularly do online - buy pizza, check account balance, etc. However, it is not good to conduct in-lab usability testing when specialized people with intrinsic motivation for completing a task are required.