Why is Speed Buster put at mach 13 here when that's just the name of a boss theme? It's not called the Elephant Cannon either, it's the Buster Launcher. If you go by wiki then it'd be a particle beam which goes near the speed of light and one that massive would be
much higher than town level considering they carry kinetic energy and the blast is enormous, though I have yet to find a proper source that it's a particle cannon though the Buster Launcher does partially resemble a particle acceleator with its tube appearance and we can at least tell it is radioactive

. It also did not "destroy part of a town", it only destroyed a big rock (albeit without a trace at that).
Travis has also dodged lasers from Destroyman and there's no way they are anything but lasers with the way they look and act (shooting in a straight line, burning what it touches).
There's an amazing speed feat in Charlie MacDonald flying into space in what may be one frame

or mere milliseconds here
https://youtu.be/5NJIKS8_ipg?t=402 and
Also what of Glastonbury throwing Santa Death Parade at such speeds as this? This would work as a good feat for Glastonbury considering it's just rated at the same level as Travis.
https://youtu.be/vqWl2GaaMfk?t=689 Because this would also yield more than town level.
If we could get a proper source on Speed Buster's weapon being a particle cannon we might be able to get consistency with the "magnitude 20" Dr Letz Shake statement (that I reiterate he can limit the range of as shown ingame) for all we know if we can quantify a particle beam's power through its sheer size or support the later "destroy the world" statements in Travis Strikes Again.
Also Darkstar can make a very violent earthquake just by swinging his weapon into the air
https://youtu.be/qdUZEIWfGrA?t=283 nothing compared to what I said prior but still a decent feat considering how violent the earthquake is.
Speaking of lasers shouldn't Captain Vladimir's also count as them anyway? They act the same as any other laser would (again, shooting in a straight line and burning what it touches) and Travis also moves (slightly) in tandem with a literal beam of light here
https://youtu.be/OY_GmX9Szaw?t=3 and again (slightly) here
https://youtu.be/OY_GmX9Szaw?t=37 (note his blinking)
The pre-series Helter Skelter trailer also shows what looks like lasers as Travis reacts to them
https://youtu.be/wCr3zvDh7K0?t=94
No More Heroes 1.5 has the narrator call Travis's beam katana the "sword of light" so perhaps it charges up at light speed like a laser (it does look like one too anyway)? Travis can move in tandem with it easily as it never moves in one frame, take that as you will.