I have the lemo and subtank mini. No experience w the orchid v4 so can't help u there. Both are two completely different
tanks and both are really easy to build on. The building deck on the lemo is a lot larger than the subtank mini so there is room to build dual coils on it whereas the building deck on the subtank mini can only fit single coils but also has the option to pop in coils. The subtank mini has a larger air flow better for lung hits whereas the Lemo is ok for mouth to lung hits. When it comes to building on the subtank mini, personally I get a better vape rebuilding the stock occ coils rather than on the mini rba deck because of the lack of air flow and
juice channels on the mini rba deck. When it comes to dry hits, I've yet to experience any on the lemo because wicking is less finicky than on the subtank. Both
tanks have their pros and cons and you can't really compare the two because they're completely different tanks. If dry hits is your main concern then go with the lemo. Otherwise, I would get both because they're both really great tanks.