I have a little misgiving on the bottom button, but from what I hear, you get used to it .. there is also this one I've looked at :
$33.52 Mixed Poldiac Style Mechanical Mod Kit at FastTech - Worldwide Free Shipping
and if you look under the selection button, they have a different finish but similar unit for under $18 bucks ..
that has a side button .. but, I don't like to order from China and I'm still trying to decide if I want to spring for not only the mod, but batteries and a charger as well .. since I don't think my regular AA / AAA LaCross charger will work ... ???
I have the Poldiac clone that is now being sold on FT for $33.52. It is made by DaVapes and I got mine from Vaperoyalty about two weeks ago. They have stopped selling them at the present time. I don't know anything about the cheaper one FT is selling, but I would not be interested in that one for sure.
The one I have is working good so far. The only problem I have had with it is the 510 positive pin at the top is not reversed threaded and when I would screw on a tank the pin would screw down and lose contact sometimes. I just placed a #60 oring under the screw head and that is no longer a problem. I am not sure how the parts in the switch will hold up long term and as far as I know there are no spare parts available for it. It is made in China.
I really like a top/side position button on a mechanical mod as this one has. It has convinced me this is the type mod I want to be using going forward.
I am going to be purchasing a Sirius II made and sold by Vapeart in Europe. You can get the satin finish one for under $100 shipped to the US. I like the way they offer their units in that they sell the switch heads separately and then you pick which tube size you want and purchase it. So a 18350 size mod is cheaper than a 18650 sized mod. They also sell spare parts for their mods. The guy that makes and sells them seems to really take good care of his customers.