[josephholsten]

Very true! Unfortunately, your RPi is going to have only one user in responsible for traffic. Commercial VPN providers act as a multiplexer to hide who is responsible for what traffic. Ideally you'd have at least a Type III anonymous remailer mixing your traffic, but then you're dealing with much higher latency. As with everything, there is a compromise between the effort required to break a security system, the ease of detecting such a break, and the burden of using the system.

I'm not sure what point you're making about colo and transit costs. Are you saying that operating your own has higher costs? Or that a commercial VPN provider has higher costs? I'd be very interested in a price analysis that beats PIA while offering a remotely similar security profile. Keeping an RPi at your house provides defense against totally different threats.