Yes it is a nymph that I usually use under a neversink dry
The ones I typically fish in the Summer are unweighted. They don't mess with your drift much although I will wrap some lead earlier in the year or when I use it under an indicator. Also have a weighted with lead wrap and a huge cone head for really early and late when you bored and just need to go fishing even when conditions tell you to stay home.
I think your supposed to hire the guide then use them as a resource to plan the rest of your trip when fishing by yourself, not vice versa