My husband and I started out with ego-C's, and after about 2 weeks and a ton of research I took the leap and upgraded to a Provari, and I don't regret it for a second. I typically have a panic attack over spending that kind of money on something, but the reviews and feedback from members on here convinced me that it was well worth it. I've had it a couple weeks now and agree 100%. I haven't had 1 single issue and really enjoy having such granular control over my vaping voltage as well as the peace of mind of the built in safety features. The durability and craftsmanship is out of this world as well.
I've tried mine as well with a number of tanks and cartos (nothing too high end, as I'm having to budget since buying the Provari lol), so if you have any questions on a specific tank or anything, feel free to hit me up and I may have some feedback on it. So far I've tried many of the more common ones like the Vivi Nova, Vision Grande, Vision Stone, etc. The only thing I would note is that a lot of people recommend the Vision Stardust Clearomizers for vaping, and they use outside threads, so you will need an extender with outside threading if you want to use them on a Provari (some other mods as well).
My husband still uses his ego-C, but steals my Provari every chance he gets. He would get one as well, but he doesn't like the size and weight, so so for the moment we are going to get him the ego Twist, so he can play with his voltage a bit but still keep that ego feel. I may talk him into a lava tube down the road though hehe.