Dave is attentive and useful as an investor, even with 250 investments to date. He's created a brand for himself and 500 that is awesome to be a part of. It's great to be a part of the 500 family/mafia and I encourage anyone who has the opportunity to do so to go for it.
As for 500s strategy, they have money for follow-on investments. They were in our convertible note but then doubled-down in our seed round. They invest 50k in each of their accelerator companies but also do follow-on in the ones that show the most promise. The strategy makes sense to me... too early to tell because none of the exits have been smashing home runs, but I certainly expect some of them to have huge returns.