I would recommend a simple single-channel Marshall (or similar) head. Pay the extra to get a 'hand-wired reissue'. Avoiding printed-circuits, too many knobs on the front, multiple channel switching, digital reverb, speaker emulated outputs, effects loops, multiple power levels, etc. etc. sounds crazy, but will pay dividends in long-term reliability and 'fixability'. To get a variation of distortion level add one or two inexpensive overdrives, a reverb, and any other effects you like, as individual pedals between the guitar and the amp. Any individual pedal may fail at some point (although they seem very reliable these days) but the amp itself will not be compromised,
Just my own preference, which many others will probably disagree with.