Cool.  Looks like it would be neat to play with, and the price is reasonable.
I tend to view it like you do, but if I was going to try one I'd be tempted to try this 
Numyth Vulcan v2 piston.  However I don't recall ever seeing a fire piston small enough for an Aloids tin. 
Those reviews have to be fake, or all the bad reviews were deleted. 
Why do you say that?  I know that not all of their reviews are fake because I have written reviews that are posted to that site.  Perhaps they delete bad reviews but I doubt it, there are poor reviews for other products.
All in all I don't think a fire piston is a great tool.  As others have said they're fussy, they require maintenance and lube and are not super robust.  Personally I prefer a firesteel even to matches.