I work for a hosted VoIP company.

>> it was great having a perfect call connection anywhere there is decent internet.

Thats the catch. The internet service has to be good enough for VoIP. Many times, having the right router is key.

>> I'd pick up the handset and the dial-tone was immediately there;

As long as the handset thinks its registered, dial tone will be immediate.

As far as the Ooma experience goes, if you can change the codecs for your device to use something like G722 rather than the normal PCMU/PCMA or GSM, call quality should be good. What handset did you get for your Ooma service ?