The Docking Station: Consider Compatibility
Each Transformer's docking station is model-specific, so there's no mixing and matching between the TF201, the new TF300T, or the original TF101. Fortunately, Asus is sticking with $149 as the price for TF300T's complementary accessory.
It shouldn't be considered unrealistic to expect docking station cross-compatibility, especially since Asus uses the same 40-pin data/charging port on all of its Transformer tablets. The TF101, TF201, and TF300T all share the same data/charging cable and charging adapter—why not a universal docking station?
The docking stations feature the exact same layout, with USB and an SD card reader on the right, and a power/data port on the left.
Asus' documentation clarifies that its docking stations are not "100% physically compatible." Curious, we put this limitation to the test (probably to our own detriment). When we tried to plug a Transformer Pad TF300T into the TF201's docking station, we were able to use the keyboard, SD card reader, USB port, and trackpad without any problems. Physically, the only issue was that the docking latches didn't lock correctly after carefully maneuvering the Transformer Pad into the docking slot. Charging worked fine, though.
Design differences distinguishing the tablets result in a "mismatched" look if you use the wrong docking station. The TF201’s docking station design is angular, while the TF300T's features more rounded edges. If you're willing to overlook the aesthetic imperfection, this might seem like a good way for current Transformer owners to avoid the cost of an additional station. But we noticed a potential problem that should discourage you from going this route. Plugging a newer tablet into an older docking station automatically overwrites the station's firmware, suggesting an element of specificity in how the batteries for each tablet discharge. We're not sure what effect that process has, so we'd advise against it.
We covered the Transformer's Prime’s somewhat unexpected charge/drain cycle in last week's review. The docking stations feature a separate internal battery designed to work in conjunction with the tablet’s battery. Instead of draining one power source and then the other, the Transformer Prime first allows the main battery to drop to 70% charge. Then, it recharges back up to 90% using the secondary power source before letting it drain again. This cycle continues until the docking station's battery cannot provide any more juice.
In comparison, the Transformer Pad TF300T drops to 70% capacity, recharges to 90%, drops to 70%, and charges back up to 80%.
We weren't able to test whether using mismatched docking stations (for those families with multiple Transformer devices) imposes the original station's charging profile on the target tablet. However, avoid the possibility of a problem altogether and use the dock designed for your tablet.
The docking station’s internal battery delivers a considerable boost to total run time. Our browsing test suggests ~45% longer battery life.
Provided both the tablet and docking station batteries are completely drained, the tablet’s internal battery reaches a full charge first. Charging the Transformer Pad TF300F on its own only takes about 30 minutes less.