I've recently been given a 885, so i've tried to look at which stick is worth your money. I've had a ZTE 636 since launch, and it's been fine.
The 885 comes with a small bag, a neck strap to store.
885, attached to Ubuntu 9.04, works immediately. Installation in Windows is painful, & longwinded (3-4 minutes). and the control gui is usual Sierra rubbish.
I've recounted installing the ZTE on geekzone before. WIndows setup is similar to the Sierra, with a poorly deisgned telecom gui. (It's comical how in a multiple screen setup, it 'centers' on loading in the middle of two screens- yes, it spans the middle of both, and needs to be dragged before readable.....).
Ubuntu was slightly less straight forward, as you need to disable the auto-mounting vitrtual CDROM by using an AT command first, but then it works.
Connected to a Windows Vista x64 host for testing, i found the following differences., (Desktop, mains power, only firefox open, no other network connections). USB Stick attached in turn to the same port. Central Wellington Location 4 out of 5 bars for both devices, different XT Sims in each.
Pings fairly similar. 170-250 for both devices, highly irregular (down to point in time, i guess).
Highly variable transfer speeds- but when connected to the 885, i could NEVER finish the upload test on any of the NZ based speedtest.net servers - so i can't show you a result.
The 885 had the fastest measured download - over 5Mbps.
The ZTE had the feastest measured upload - over 1,5MBps.
Unsure where to point the finger and the lack of test completion on the 885.
One thing i noticed is that the 885 gets considerably warmer than the ZTE ever does.
Would i pay $99 for the 885? Probably not if it was my own money.
Although, it was recounted to me second hand by a (trustworthy) FoF to avoid the ZTE. (He was told by a telecom source). So, make of that what you will.