I am also familiar with Weka and Alteryx, but I have not used them for real-world problems.

The trouble is that so many of these products now are almost identical in what they offer you. They learn from each other. So, they compete really on marginal advantages here and there such as cost, ease of use, and ease of learning.

I know businesses that have invested in RapidMiner, but I also know that many will go for KNIME because it is so cheap. It's free. It's more cumbersome to use, but after perhaps a week or ten days, you know it well enough.

I used to work with a company where we sold a variety of products as system integrators. So I compared some product because we had to evaluate them to know the advantages and differences. At that time, we got to the stage where we were signing up with Alteryx as a partner.  

So I was in touch with those Alteryx guys and wanted to also compare their product with SAS Enterprise Miner, who we already partnered with, and with RapidMiner as well.  

A couple of customers were already using RapidMiner and we were in the process of partnering with Alteryx. We have to know the other products even if it is through secondary research in addition to what the vendors are presenting.  

We evaluated SPSS and KNIME. 

SAS and SPSS.

We did evaluate a few others like IBM SPSS. But Rapidminer is very user friendly and has a robust rating on various leading portal like KDnuggets.