Kaiser has no specific preventative care requirements and does not withhold care if you are not up to date on some schedule. In fact Kaiser works pretty much exactly like any other HMO with the main difference being that insurance is in-house (but a different department, so insurance screwups still happen, but at least the hospital and the insurance are not constantly fighting each other with you stuck in the middle).

Well that and with Kaiser it's a lot easier to tell who is in network (they never commingle in and out of network care).