Hairneva looks like a good clinic from what I've seen. I also considered different options before making my decision, and I ended up having my hair transplant at Istanbul Care. I'm happy with my experience so far. I'd recommend comparing both clinics and looking at real patient results before...
I haven't personally tried Estherian, but you could also look into Istanbul Care as another option in Istanbul. I'd compare the actual patient results, graft numbers and who performs the procedure rather than focusing only on the price.