Have used ProTA for many years now, but currently with version 3.25 and reluctant to move to version 4 because of what I perceive to be a less friendly (read more complicated) interface. Admit to having giving version 4 demo a brief trial only. Since you consider version 4 to be altogether different I would be interested to learn whether/why you find it more effective than version 3. Agree that writing complex, yet useful and workable formulae is extremely easy in version 3 once you have mastered the basics, and also agree that support is usually both prompt and helpful.
