what is some signs that an opti spark might be on its last leg ?

would sluggish starts be one of them ?
it's got around 80k on it and a brand new battery. when i always start it, it grunts really bad like the battery is almost dead.

thanks

 

that more sounds to me like your like your starter is on its last leg, make sure all connections are clean and tight and make sure your engine ground is good if all those check out and its still doing that pull the starter and take it to autozone and have them test it for free