My experience with the Banggood Arduino micros is that they have really sketchy reset buttons and may be running an older version of the bootloader.
They basically work, but they appear to be unlicensed clones using the Arduino mark without permission.
Good to know I will come back after I receive mine. Besides the Olimexino-32U4 I have an original UNO R3 SMD and a Fake Mega 2560 and UNO R3.
One of the reasons that I went with this purchase was that the website did not claim that this is an Arduino licensed product but rather just compatible and the picture did not show any Arduino links or trade marks.
I don't see any need to get worked up about it either. Leonardo etc. programming works great if you stay completely within the Arduino universe, but any arguments here are considering a n00b wanting to simply load a .hex onto a device. Teensy wins on that count, no question. OTOH it's not super hard to get avrdude working, just a bit cryptic for a n00b, and once it's working it's almost as easy to reflash as Teensy.
I find it terribly annoying on many boards and channels. As soon as someone who is not part of the established old guard says something or asks something that shakes the jeopardises the status quo of the perfect world according to them hoards of chiwawas come out to yap at the heel. Gets tiring.
I think having a variety of '32U4 boards is great, to fit different needs. Even made a thread about them 
Cool work! Bookmarked. Been spending some of my limited free time getting my head around USB and the Linux input stack. To date, from an electronics perspective, to date, I have only toyed with some code for Arduino. I do have plans for a handful of projects and may want to move away from Arduino and graduate to coding directly for the avr or pic, which decision may boil down to flexibility of the development environment on Linux.