Sauce Labs is an amazing product for the work that I do, and there are many different solutions for testing out there. Sauce Labs in particular, I have used on many occasions within different roles and I found it to be a good alternative to options such as Browserstack.
The most important and valuable feature is the ability to select multiple browsers and environments to test and configure how your site runs and works. This process eliminates the need for any virtual machines taking up disk space on servers, and now Sauce Labs streamlines the testing process by being able to have these virtual instances of OS and Browsers right on-demand.
I particularly found the tabbed view of Sauce Labs useful, allowing me to have multiple browser sessions open (one for, say, each operating system as well as different browser brands) along with its clean and minimal interface. These are features which aren't found in other testing suites and are definite bonus!
As a newbie to automation testing and having experience in using a wide range of on-demand tools, my main aspect of Sauce Labs involves using the 'Manual Testing' option, which is brilliant. You simply selected the URL and choose the browser and environment, and within minutes you'll simply have a virtual environment to play with, and it is really that simple.
Another useful aspect of Sauce Labs' product is that you can allow it to take screenshots, videos and logs, which are really, really handy. Having dealt with many issues that end users see whilst a website is being developed on, often is the case that issues are hard to replicate. Knowing Sauce Labs is there to record this (in case I can't replicate it), makes this a tool which you can share the experience with other users.
The configuration and options within Sauce Labs are endless, which makes it an excellent product. A well-designed and minimal interface has also helped me to stay productive and keep focused on the main tasks which I use it for (manual on-demand testing and using different environments to see expected behavior for our platform).
Over time, I aim to expand into the automation area which looks great from the outset and be able to automate some tedious tests which could reduce the amount of time that I spend testing, and ensure I can continue to capture bugs and issues more effectively.