It's fairly normal for signal to fluctuate which causes data speeds to vary. You can learn more about signal fluctuations here: http://support.t-mobile.com/docs/DOC-5181
To make sure things are working as they should be, you can use this document for signal troubleshooting: http://support.t-mobile.com/docs/DOC-4211
And here's some information about data speed capabilities: http://support.t-mobile.com/docs/DOC-2779
We did check the network in Toledo and it looks like your area has a good variety of speeds and strength, some not so fast, some very fast. The balance between the two can be rather delicate; your device works hard to use the best available signal. You may be able to modify the mobile networks that your device uses primarily in the settings. Access settings, then more settings, then mobile networks. If you see an option for network mode, you should open that and choose the arrangement that you believe will work best for you. Of course, automatic will give you more consistent signal availability, but the signal may be edge, or 4G, depending on what's strongest.