I tried three other mapping plugins and all are pretty good. I could probably have lived with them. Until I found this one!
The import feature is very well done and the import templates (in multiple formats depending on what you need) are excellent and have everything you will need. (Import Export is for the Pro version, which is priced well). Layers are great. The markers can be expanded using free open source graphics (see documentation). The support is fantastic — I am currently in the 30 day free trial of the Pro version (planning to purchase) and I even got personal support as a Pro trial user! I sympathize with anyone who has had a negative plug-in experience. We’ve all been there! But if you have a problem with this plugin you should go to the support forums and ask for help. It is quite a complex plugin with hundreds of options and setting and not everything is immediately apparent.