How do you know you can use a custom filter switch

I have a Marantz 8260 CD(SACD) player. In the owner's manual, it says that the filter switch on the back of the player should stay in the standard mode as opposed to the custom mode unless you know that you have an amp that can handle the SACD signal. It says SACD mode sends out a much stronger signal that could damage your amp. My question is can I flip that switch from standard to custom mode if I am using a 100 watt Adcom 5400 amp pushing 1.5 maggies. Also, does this custom mode switch really make a difference on SACD's?
The (slight) risk is that the increased ultrasonic energy might adversly affect the amp or more importantly the tweeter. With the Maggies and the Adcoms this shouldn't be an issue.

I don't think you'll have any problem.

BTW I use a Sony SCD-1 into Apogee Studio Grands (full range ribbons) and run with the filter in custom mode, no problems.

The sound seems a bit more transparent without the ultrasonic filter in circuit.