Methanol injection to me , is not worth the $$$.
the system itself is more expensive than NOS system already
the gains = very lucky if can even touch 5 hp for N/A
Nitrous Oxide is nice
but problem is , even running 55hp dry shots, it places quite a bit of stress on the system.
and additional (complicated) tuning is required by the EMS system to retard timing everytime Nitrous is injected.
Worse case is:
a) Nitrous runs out, and your EMS still retards the system = real power loss
b) nitrous punches in , system not retarded, piston's surface crack
and Nitrous is expensive AND addictive