Throughput vs. Path Loss
Since I had the data, I thought I would compare the G2 against the last WRT54G version that I tested, the notorious V5. Figure 10 shows the downlink comparison, which shows the V5 beating the G2!
Since these measurements were both made with direct connection to the routers and a near-field antenna on the clients, the differences are not due to the internal antenna design of the G2.
Figure 10:WRT54G2 vs. WRT54G V5 throughput vs. path loss - downlink
Similar results are shown running uplink in Figure 11, with the V5 once again maintaining higher throughput longer than the G2 and ending at a higher path loss (lower signal).
Figure 11:WRT54G2 vs. WRT54G V5 throughput vs. path loss - uplink
So if you own a WRT54G V5 and replace it with a WRT54G2, you might actually see slightly shorter range.
It looks like Linksys is fully committed to the new "stingray / UFO" (my moniker, not theirs) design with internal antennas for all consumer wireless routers—at least for now. My testing showed that the G2 is pretty much the functional and performance equivalent of the WRT54G that it will replace (although with a routing throughput boost), when stocks of the WRT54G finally run dry.
Successfully transitioning a top-selling product is definitely tricky business. You need to keep the things that got you to the top-selling spot, while tweaking features to keep the design fresh. The path to the G2 hasn't been without its losses, namely the legions of folks who prefer DD-WRT, Tomato and other alternative firmware to the factory versions. And the switch to internal, non-upgradeable antennas will force buyers who want the option of using higher gain or directional antennas to other vendors.
But Linksys made the transition away from alternative firmware a few years ago by switching OSes and cutting back RAM and flash memory, forcing firmware-replacers to seek other options or move to Linksys' WRT54GL, which was created expressly for the hacking crowd. Linksys is leaving, at least for now, the GL as part of its lineup. So if you prefer alternative firmware, you still have a Linksys option.
This leaves the G2 free to take its place as the go-to router for consumers who want basic Wi-Fi connectivity and who likey Linksys.