Yes, definitely many upsides to this, BUT, there are downsides as well. If there are multiple heirs and multiple assets (brokerage, bank accounts, real estate, life insurance, etc), then it is actually quite difficult to keep track of the big picture of how much everyone stands to inherit. This is important if the goal is that everyone gets the same amount or a specific percentage. Case in point, my DM (5 children) wants to allocate a certain percentage to each of her heirs. She is 90 and mostly invested in short term CDs plus some real estate. She is into chasing yield, so at virtually every maturity date on of her 10 or so CDs, she will switch banks. While she is very sharp for her age, she does manage to mix up beneficiaries during such transitions, especially when more than one is due at the same time. So, once or twice a year, I try to help her sort it out and rebalance her allocations. To add insult to injury, she also has been known to change her mind (on a whim) on the %-ages for each heir, so that complicates the situation even more....
I am her designated executor, and I have come to the conclusion that it would actually be much simpler for me if she pulled all the TOD allocations and just just let me take it all through the probate process. Alas, she insists on keeping and (mis)managing the TODs....