The analogy goes like this. The Droid is to the iPhone what the PC is to the Mac. One is open and, as a result, less stable but offers far more choices. The other is limited in choices, but admittedly more stable.
I personally prefer more choices, which I am fairly certain will be the case on the Droid within a year or so.
However, with choices and flexibility, come responsibility. Being a software developer and not terribly needy about having lots of games and every app on the planet, I feel confident that I can install a mix of apps which run in a reasonably stable fashion.
For example, I installed SportsTap, which, after running all night, caused my system to slow down big time. So, using ATK, I killed it and then uninstalled it - simple as that. Haven't had any sluggish issues like that since then.
I'm currently trying to figure out if the Dolphin browser is well-behaved. Overall, it seems to be OK. But on occasion, it seems to get greedy and start causing the system to become slightly jerky. So I use ATK and kill it - no worries.
Bottom line: Eventually, I'll end up with a set of apps that work well together and meet all of my requirements. Until then, I don't mind having to babysit the mix of apps on my Droid, occasionally having to wack the ill-behaved one.