I don't know if I'd call it a nightmare... but the ones I've seen are not 1:1 of either the V1 or V1.5 Omega.
The most common complaint I see with Omega clones... is users trying to fit coils into the "Chinese standard" one-size-fits-all, too low post holes - down inside a deep well. If you're new to the RDA thing... I'd imagine that can be really frustrating.
The original Vapor Bombz Omega had no post holes, and was designed to easily capture the wire under the screw heads... and even use a - looped on the center post/single piece of wire - coil set, rather than 2 separate coils, if you choose.
People .....ed about capturing wire under screws with the V1 authentic Omega... so the V1.5 has coil holes - but up pretty high on the posts, so fitting is still easy.
If you don't have thick enough post shoulders to capture wire under the screw head, you can drill new, higher holes - or you can fit washers under the screws to make screw retention more of a possibility... if drilling isn't in the cards.
Although not my cup of tea, you'd probably be happier all around with an "easy build" RDA, like the Plume Veil.