I’ve never used any blendco products but have heard good things about them. I’d say if you feel some of their products are not working/performing as well as you would like and/or if the costs are becoming prohibitive to maintain, then that is when it is a good idea to shop around. You also want to make sure you have exhausted the possibilities with your current supplier and chemicals line with regard to product choice, dilution, etc. If you are still coming up short, that would be the time to make a switch.
I’ve switched things out many times over the years - mainly when I felt that there were other products that became available that could outperform what I was currently using, or when a more “updated” or “next generation” type of product came out.
For example, when Simoniz came out with their hot wax, it was one of the early carnauba products and I saw it was making a visible difference on cars and operators were making nice profits on it, so I started using it. Eight years later, I just switched to Shine on with Vantagloss by Quest because I had heard - mainly on this forum- that Quest was using some new polymers and producing top notch products in the sealant and protectant category. I tried it and it is definitely an step up from what I was using. The switch was the right thing to do for me.
That’s how most of my chem changes have happened over the years. But sometimes doing nothing is the best thing to do too.