I've found that user forums are usually the source of reliable information and that users often have a more in-depth knowledge of the real life use of a product than the product's creators.
Of course I could just experiment to find the answer to my question. However, I know nothing about VoIP devices. Right now, my Obi202 and my Callcentric setup are functioning without problems. I'm reluctant to take a chance on messing anything up. For example, could experimenting with removing the USB wifi cause me to hear:
A) Oh, didn't you know if you remove the USB wifi you have to reconfigure the device?
B) Too bad. The wifi device resets chip #38hhii5 and your device can never work again.
c) Didn't you remove power from the Obi and let it sit for 20 minutes to drain the power capacitor? It's power feed is reset when you install the wifi device, and unplugging it as you did fries the power chip. Too bad.
I know that A, B, and C are nonsense, but I like to look before I leap - especially if I haven't dived into a particular pond before.