There are several models, some with more features than others. Be sure you're comparing apples to apples. I really like the dial-back feature on timing advance to check centrifugal and vacuum at cruise speed, and plotting the advance curve by carefully increasing the speed a few hundred RPM at a time.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!