The box mine came in just said "Portable Mini Mixer" and "Made in China." There's no branding on the unit, either. I agree the Sper Direct base unit looks identical to the Norpro, but the sticks mine came with are notably thinner gauge (and they don't have the cuff on the attachment end).
It might be worthwhile to buy the Norpro for the extra attachments, which might make the mixer more multi-purpose. If the Norpro stirrer is too thick for some of your bottlenecks, you could always get the skinny ones from Sper. They'd probably fit the Norpro mixer too...at least I'd hope so.
I think it was someone with a different type of mixer who couldn't fit it in smaller bottles - I've never had problems with any of mine. I'd like to try out the extra sticks just to see, but as they're $34 + $20 shipping on amazon.ca I think I'll pass.
I don't have high hopes the unit will last long, it fairly cheaply built.
Yes, I have to agree with you there. I don't think it's in it for the long term.