Luvya, I recently considered my options for a portable amp, primarily trying to decide between a SuperMini and a Meta42.
The general impression I got from those who responded (and from other threads) was that the SuperMini (v3) is a great headphone amp for the price (100) and the small size, but that it's not as good as a Meta42. It occupies a useful niche, but I decided to pay more for a meta42. I do need something portable, but as long as it can fit nicely in a pocket, that's fine. Something smaller than that, while nice, isn't likely to be any more useful. And I wanted to be confident that my amp could drive even high-impedance phones loudly and cleanly, if so desired. The SuperMini may do this fine, for all I know, but I chose to take a small chance in buying something more expensive that I may not need, because hopefully it will provide me a greater chance of being satisfied with my decision.
It's nice to have options, isn't it? Sometimes a curse, especially for indecisive bastards like me. If you decide on a meta42, you'll have even more options to face, regarding components. Of course, you could let your builder choose the best option for you, given your criteria. In any case, if you do decide to go with a meta42, you should consider KurtW as the one to make it for you. He will be building mine, and has been very helpful (read: putting up with many questions) along the way.
piece,
rp:AUM