Whales can dump at any given time, I prefer when there is a large community of average investors, then token price will be more stable.
Well let them dump menapay, i think the menacash serves that purpose of stability, meanwhile you could pocket cheap menapay

Security tokens tend to dump less. Because unlike utility they are backing with some real value (profit share of the company) so dump can happen of course but if it will, i expect a limited dump.