Switched from a 2014 Newport to the 2018 Newport 2 (insert) because of the lack of feedback on the 2014 deep mill. I've hit pretty much every scotty you can hit - tour issued and off rack, and I love the feel of his inserts (specifically the 2018 line). The reason for the insert was to gain a certain sound and he really nailed it. I can easily diagnose all mishits - hollow if struck off center, and pure when struck out of the dead center. The insert truly helps you diagnose where your miss-hits are. If you're a good putter and you hit it out of the center often, there's no reason not to like this putter. I will say I did not like the fastback/squareback models as much. The feel was a bit more dead with the aluminum - BUT - I didn't mind it at all and many on the pro tours, on the ladies and mens side still use them (I.E., emily pedersen, matilda castren, etc.)
There are many on tour that still game the "worst scotty's ever"...for as much hate as they get, Nelly Korda and current world number 1 gamed a Newport 2 with an insert and won often with it (currently in a special select squareback 2), Sei Young Kim games a Newport 2 insert and won a major with it, Brian Gay won in Bermuda with a NP2 last November, Sung Kang games a NP2 insert, as does Chase Koepka, John Merrick, Hugo Leon (european tour), Andrew Kozan (recently turned pro), Will Grimmer (Korn Ferry Tour), and several others actual use off the rack 2016 newports with inserts (john vanderLaan on the Korn Ferry Tour), Kelsey Macdonald (european ladies tour)...they obviously feel right to some of the best out there and again, it's all personal. Typically, the guys and girls that find the center of the insert might like it more - if you struggle to find the center, that may be a reason the feel is off for you.
Lot of hate on the inserts, but I can't go there. Scotty Cameron just makes quality putters and no matter what they all end up in the bag of amateurs and pros alike for different reasons.