|To do it properly, you can't (shouldn't) avoid a crank mounted sensor or similar (flywheel etc).
Having a crank mounted sensor and a cam sync is the only way to achieve very accurate timing, which is more and more important as we start pushing numbers up.
Personally, I use the Ross 36-2 in your first link, with a Cherry sensor on a simple custom bracket.
For the cam side, I use a GT101 sensor on another simple custom bracket, with a NZ wiring cam mounted single tooth trigger disk.
Total cost breakdown (from memory)
Cherry sensor: $80AUD
Bracket: free scrap metal
GT101 sensor: $80AUD
NZ Wiring triger disk: $80NZ
Basis of sensor mount and bracket: $25AUD (generic GT101 sensor mount slightly modified, bolts on to cut down CAS bracket).