Radio interference is a common problem, particularly in fuzzes. The op amp circuits are much less prone to it. I get non-specific noise (ie not a radio station) on breadboard circuits but haven't had a problem with stripboard at all. According to AnalogMike, a small capacitor from the signal input to ground can help filter out these very high frequencies.
The chime amp would be a good option if you want to avoid stripboard.
My next step on this build is to cut a hole in the enclosure top. I have some thin MDF that I will cut to size and paint to use as a control panel. The cabinet walls are too thick but I don't want to put everything on the back panel. If electrical interference becomes an issue I might have to do something creative with metal foil, glue, and tape to shield inside the box. I am hoping the low-gain, low power circuit wont be too prone to noise.