well, Andy has pretty much answered your question quite thouroughly.
I'd just like to add that LGB's may also limit your delivery profiles. Again, depends what target, what threat etc etc. When you understand what you need to destroy the target, understand what you need to do to stay exposed as little as possible while increasing your MAP, and put all these (plus more factors) together you'll see that yes, there are many instances where you shouldn't really wear LGB's, and many others where you should;-)
Sorry for being vagues, but somethings may need more than a post o explain fully;-)
Cheers!
Angel
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Angel
Virtual Hellenic Air Force
http://users.groovy.gr/~dtra/111vfw