Does the quality of a customisation matter?
Like any other product or service, the quality of customisation too matters. A customisation when not done properly, may cause a lot of issues in Tally. Also, when there is a software update, customsation may have to be reinstalled. Thus it becomes important to get customisation done from a trusted service provider who has the required experience and knowledge.
Service provider plays a crucial part in Tally ER 9 customisations as you may need support for migration to newer versions of Tally ERP 9. And if the quality of the customisation is not good it may affect the efficiency of your Tally software.