First of all, I would never buy second hand coilovers online. It doesn't matter how much info the previous owner states about them, you simply never know what condition they're in. You're just going to end up getting blown coilovers regardless, and dealing with rebuilding them will be a PITA.
However, given the choices that you're looking at, the JICs are the best of the bunch for a couple reasons. They're adjustable inverted monotube struts and are both preload and height adjustable. On the downside, JIC as a manufacturer has a history of being shady when it comes to rebuilds and even the actual quality of their products... basically, they don't give a fuck about their customers.
The TEINs are straight garbage, don't even waste your time. As much as I have read about them, people talk about how messed up the dampers are when they put them on shock dynos. Not to mention, they aren't "full-tap," meaning they aren't height adjustable aside from fucking up the spring preload.
Yes, Ohlins make great products, but that setup you're looking at is all wrong for what you seem to be interested in. Progressive spring rates are great for a car that sees public roads more than tracks because of the forgiving ride quality. Linear spring rates, However, are a must on the track... research the difference!
In my opinion, save your pennies for a nice new coilover set with exactly what you're looking for. Ordered from best to good on my list would be: Zeal, Silk Road, KW, H&R, Cusco, Tanabe and JIC. Helper springs or not, a good set of coilovers have Linear primary springs, full-tap, preload, and dampening adjustable.