OK, the plot thickens!
First of all, x220forMe, thanks for your reply. I've captured the info you requested and pasted below, but I don't know that it matters now.
I seemed to have gotten past this problem. Here's how...
I switched the activation from Sprint over to Verizon.
On Sprint, in the same location (my office) I was only getting 4 bars (of 5) and very slow...about 500 to 700 kbps down and way too slow to mention upload speeds. :-(
On Verizon in the same locaiton (office desk), I'm getting 100% signal (see info below) with MUCH FASTER results.
A speed test (speedtest.net) indicates: 2.40 MBps download and 0.58 MBps upload.
Those are more like it! Exactly what I was expecting from an embedded device.
Maybe it's just that Sprint isn't strong enough here? I thought at first that might be the case, but when I was out at meetings and testing from an outdoor location in an urban environment where Sprint shows full EV-DO Rev-A coverage on their map, I was getting the very same slow speeds! I still cannot explain it.
Nonetheless, I'm leaving it on Verizon and enjoying their much faster network and far batter coverage. Only reason I chose Sprint was because that's what my previous Sierra Wireless AirCard 402 (ExpressCard) was and when I gave that up to get an embedded Gobi 3000 chip, my IT department just switched over the Sprint activation to use the new device IMEI/IMSI, etc. I wasn't aware that they were still able to activate our employees on Verizon and we were...so I had them switch it.
Moral of the story: Beware when using Sprint with the Gobi 3000 embedded! (Sierra Wireless MC8355)
C:\>netsh mbn sh cap int="Mobile Data"
Device capability information for interface Mobile Data:
-------------------------------------------------------
Device type : Mobile Broadband device is embedded in the system
Cellular class : CDMA
Voice class : Simultaneous voice and data
Sim class : SIM is logical or embedded in the device
Data class : 1xRTT, 1xEVDO, 1xEVDO REVA
CDMA band class : 800 MHz, 1900 MHz
SMS capability : PDU receive, PDU send
Control capability : Hardware radio switch functionality available
Configured for mobile IP with simple IP as fallback
Manufacturer : Sierra Wireless Inc
Model : Sierra Wireless MC8355 - Gobi 3
Firmware Information : D3600-STSUVH-1576 0d010008
Maximum activation contexts : 1
C:\>netsh mbn sh conn int="Mobile Data"
Connection information for interface Mobile Data:
-------------------------------------
Interface State : Connected
Register State : Home
Register Mode : Automatic
Provider Name : Verizon Wireless
Provider Id : 00000
Provider Data Class : 1xEVDO REVA
Number of connections : 1
Serial number #1
Connection Id : 3
Access Point Name :
C:\>netsh mbn sh sig int="Mobile Data"
Signal information for interface Mobile Data:
-----------------------------------------------
Signal : 100%
RSSI : 31
Error Rate : 0
Rssi interval : 30
Rssi threshold : 5