Powder is so easy to use, more compact and lighter than equivalent amounts of liquid detergent. I’ve never had any problems with the powder dissolving in a regular wash cycle. It really isn’t any harder than using liquid or pods.
There are many varieties of powdered dishwasher detergent. I’m most concerned about getting rid of the demand for plastic containers, but there are other toxicity considerations, so you might want to check with EWG at https://www.ewg.org/guides/subcategories/24-DishwasherDetergent
Problems: I found some complaints online about powder caking and the issues seem to be the detergent door not opening properly or something being washed that blocks the door from opening.
PODS- There are varying opinions out there and some think the covering can break down to harmless substances. Whether or ot this is true- WHY are they sold in plastic containers?? Makes no sense to me other than there must be something that drives the manufacturer’s profit!