Is it true that ANY Android phone can be used for App development and testing? 

I'm trying to find some inexpensive off-contract hardware for development and testing of our Apps. I've found some devices I can buy New with No Contract for $150 to $300 (like the HTC Aria or the Huawei Ascend). Is there anything that would prevent me from using these devices for USB debugging and app testing? I guess I'm concerned because I've read how the HTC Aria has been locked down by AT&T to limit applications. I suspect this won't affect me loading apps using ADB, but I'd like to be sure.