I have used many years SD1 and I stil think that it is great overdrive. Ok, Hot Wax is more expensive, but result of using id is perfect. At first, it sounds vintage, but it is possible to set it modern. Another thing - many stompboxes are doing almost everything, distortion, overdrive, metal (it is music genre not sound efect) even fuzz (come on!). Hot Wax is only overdrive with plenty of "colors". Ok, sometimes it is similar to distortion but distortion is result of overdrive so... 
 
Pros: 
vintage sound 
valve taste 
very strong distortion 
nice design 
great possibilities for customization 
meaningful price 
 
Cons: 
None 
 
I have tested it on: 
Fender Stratocaster Deluxe 
Gibson Les Paul Faded 2018 
Marshall DSL40CR 
Marshall MG10