Does using third party controls like DevExpress in windows forms, wpf, etc increases/decreases processing time and memory consumption ?
They surely do increase ease of development.
Their support online is also limited, unlike the native controls which Microsoft provides.
Is using them worth the cost ?
Just consider the time alone you will spend on creating a custom control and making it work, that has already been created by n vendor like
DevExpress, saves you money.When it comes to the controls them self it all depend on your needs. I found
DevExpressexceptionally good. The ease of working with the controls are better then it’s competitor, but then again, a well polished Dev with sayC1controls, would disagree.When it come to report designers, C1 is extremely slow.
Devexpress’s designer in WPF is not so good. Very buggy.
Infragistics reports can be build cross platform, so that is n a MUST have.
It all boils down to your specific need. If you have the money available, then it will be a good investment in the long run.