The variance on BCH is can get pretty bad due to sharing SHA256 with Bitcoin and 3% of the price, recent example 1 block per minute on average 16 blocks
Normally, newbies have serious misconceptions when it comes to crypto transactions. You need to differentiate propagated/unconfirmed and n-times confirmed transactions.
An example where the 0-conf can become an issue is here on memo by reaching the 25 action limit, that limit can be increased in time, variance not an issue for 0-conf in general.
Block variance not a problem for any place and service that can accept 0-config, small and quick amounts works great for that. Only observation is that block variance is higher now.