The Bladerf is very easy to use. Good documentation. Pre-built binaries for the firmware and PC side APIs. I've used the C API extensively on Windows. Unfortunately as with pretty much all SDRs, the RF performance is pretty bad (spurious/images/etc). IIRC it has some odd limitations on the anti-aliasing filter and was quite CPU hungry at higher tx rates. You're not going to find an SDR without quirks though.