I'm pretty sure, that with 90 Ω impedance, the Tzar 90's would benefit quite largely from some amping. As far as amps go, it all depends on his budget, but he will need one to get the most out of them.
Exactly. I'd be hard pressed to find other $40 iems that perform this well. In all honesty, these are worlds better than the original iPod ear buds. If I had to put a price on this sort of performance, I'd put it around the $70-80 range. Not spectacular. It certainly won't come anywhere near multiple balanced armature IEM's or even single-BA iems. But, it's a great value for the price.