The HR34 is RVU compliant, but I don't know if that is actually working in the real world yet. Even if it is, you would need RVU compliant tv's at every location and even then you would only be supporting five of your eight locations. Using four regular DVRs, you would only be supporting four of your eight locations. Using four DVRs plus four receivers would cover all eight locations.
Right now, you would want to consider either one HR34 and seven HD receivers, one HR34, one HR2x DVR, and six HD receivers, etc. The HD receivers will let you watch live tv at each of the tv locations, as well as allow you to watch recorded shows from either the HR34 or HR2x series DVRs (which can also watch from each other).
You need a DVR at any location where you want to be able to pause, rewind, fast forward live tv.