I agree that the UI is less responsive but it's not much of an issue unless you mostly place your bets on their live odds together with the cashout.
The live odds are what I usually bet on in betting sites which is where I faced a ton of issues due to which I stopped betting there completely. The worst thing is that these issues continue to persist despite so many people complaining about them.
whenever I have encountered any problem with Stake their support staff have quickly provided a fix for it, and as far as their sports book is concerned I feel that they’re doing decent promotions to attract the gamblers to wager out there.
I guess you don't bet on live odds a lot then. Also, the lag in their book can be observed in their casino games as well on a regular basis.