A CZ-5 for 100 bucks is a steal and yes, you will notice the difference from your BH. Simple test, drop a square pulltab, nickel, dime and a gold rring on the ground. Turn the disc to 1 on the CZ, sense to 4 and see how far you can get the coil above the targets and still see a valid ID indicator on the CZ. For the time being set the GB or ground balance to 5. If it beeps consistently over each of the targets and gives a consistent indication on the meter at up to say 8" then would you be surprised? I wouldn't be surprised and I'd buy one for 100 bucks if it didn't work. As long as there's not broken glass, rust or contaminated battery contacts and the coil is not cracked, go for it.