IMHO:
River is a great, customer friendly company. I’ve used them for a while and never had a hiccup with any purchase (DCA or smash buy) or transfer to a cold wallet. The few times I’ve needed customer service they were easy to reach (an actual person)…. I even got Alex Lieshman (the ceo once)🤯. This is one of the most convenient financial services companies I’ve ever been involved with. 

I used river and one of their primary competitors for ~ 1 year (my first year as a bitcoiner). The other company was also very good but there were several interruptions in service (both for purchasing and transferring). As a newb bitcoiner I found it very stressful  during these episodes. 

Long story short for the last 1-1 1/2 years I’ve used exclusively River.