I would add that abusing turbo switches (in some games) is akin to abusing continues. You don't TRULY appreciate some games when you're a lazy slob. For example, IMHO: Arcade Ports should NOT be played with turbo unless this feature was available in the arcade version.
Why? I feel that it betrays the original design of the game. Some games, for example, offer power-ups that increase the frequency of your shot. Other games have a "Hold down button for charged shot" mechanic that totally breaks when you use turbo switches.
I know some folks may not agree with me, and I certainly don't follow this all the time (i.e. if I am frustrated and just learning a game), but I generally follow this rule.
Fundamentally, unless the arcade version of a game offered turbo-fire, PUSHING THE BUTTON SWIFTLY is one of the fundamental skills that shoot-em-up fans should possess. You cannot consider yourself a connoisseur of the genre if you can't obsessively press the fire button when necessary.
Monster Lair for example, is best with NO TURBO, because each weapon has its own UNIQUE "frequency"... Missiles travel farther when you hold the button longer, the spinning shield power-up has a VARIABLE frequency (it is fun to slow-down and speed-up the shield, offering regular or double-thick shields). Lots of games (all genres) possess attacks with unique timing issues (Legendary Axe I & II !!)...
These nuances are lost when you abuse Turbo switch.
16-SHOT!/end of rant
P.S. I apply the "no assisted turbo-fire" rule to most games, in all genres, and most shoot-em-ups (not only arcade ports). That said, there are still plenty of games I'll use turbofire for. I'm not perfect (or completely insane).
Also, I pretty much agree with what people have said since my last post.
Thank goodness
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