Regarding spike back protection, I think it best to explain why..... Everyone should understand the protection parameters of their battery's BMS. The BMS is there to protect your batteries, from High Voltage, Low Voltage, Over Current, Low Temperature, and High Temperature. The BMS protections vary greatly between brands , but that should do it for most. So, lets say your Alternator is charging at 28.4V, that's great if the BMS's High Voltage shut of is at 29.2V. But, what if have a spike in the alternator's charging voltage (above 29.2V), or some type of failure in the battery's BMS...... your BMS will turn the battery off, and then your Alternator is instantaneously looking into an open circuit. AND, You just smoked your Alternator.
This device should help anytime BMS shuts down your batteries, including your Victron Charger would feel less stress when the BMS does it's job.
In theory the $99 device Bill mentioned should save the alternator in this scenario. I didn't think about this, but this device makes a lot of sense.