You get the capability of either 3 or 4 channels (depends on your area)streaming to your house at any given time. This is the limit of the adsl bandwidth at this time. You can have all 6 boxes watching the same channel and will be using only one of the streams. Have 3 different channels showing on any combination of the 6 boxes and you are using all of your streams (unless you are in an area that gets 4 streams at once).
Remember that anything recording is using a stream although that stream can be watched on any box at the same time as it records.
If all 3 or 4 streams are in use by the PVR or set top boxes, you can't turn on another box to watch something that isn't currently on one of the 3 or 4 streams currrently in use but you can watch anything that is already recorded on the PVR. Watching fro mthe PVR is not using a stream to the house.
Remember that anything recording is using a stream although that stream can be watched on any box at the same time as it records.
If all 3 or 4 streams are in use by the PVR or set top boxes, you can't turn on another box to watch something that isn't currently on one of the 3 or 4 streams currrently in use but you can watch anything that is already recorded on the PVR. Watching fro mthe PVR is not using a stream to the house.