Just to add some confusion - err, information - the Meguiar's G110v2 is also an alternative worth considering, as against the PCXP or the GG6. I recently bought a DA polisher myself, and was choosing between the G110v2, GG6 and the PCXP (the Flex 3401 was way out of my price range). Here are my thoughts about them, based on everything I'd read (and since validated when I had a chance to use all three DAs, along with the Flex):
- The G110v2 is the most expensive of the three, and it's reported to also have the best build quality. It does not have as much power of the GG6, but the cruise control feature helps it keep the pads spinning. There were a number of reports of issues with power cord failure, but the latest release has supposedly solved this problem, and I've not read any other issues with this polisher.
- The GG6 has the most power, and is not much more expensive than the PCXP; it has a lifetime warranty. There have been numerous reports of this polisher breaking down, though people have had no issues getting these defective polishers replaced. Quality control also seems a bit erratic; people who've had more than one GG6 have reported variances in noise, vibration, and power.
- The PCXP is the least expensive of the three, but is also generally considered as the least powerful. Its cachet has always been reliability - Porter Cable is a known power tool manufacturer. In the past several months though, there have been reports on the various detailing forums of problems with the polisher, mostly relating to the shaft - either their quality has gone down, or they have a bad batch out there.
In the end, I went with the G110v2 - primarily because of reliability. With the cord issue now fixed, the G110v2 appears to be the least problematic among the three, and that's a big deal when I'm living halfway around the world (and therefore cannot easily avail of warranty repairs); while extra power is always nice, as a hobbyist, I can afford to spend an additional half hour or so polishing.
However, my decision could easily have been different, under different circumstances. If I was living in the US, and was a hobbyist, I most likely would have gone for the GG6, as you can easily turn the polisher in for replacement under its lifetime warranty. If I was buying for a detailing business, and had the money for it, I'd go for two of the GG6s (so I have one spare in case my main one breaks down); if I can't afford that, I'd then go for the G110v2.