As I was saving up specifically for this guitar (long and good experience with Yamaha guitars, and previous experience with Yamaha's SRT pickup system), this review may be somewhat biased.
As my title says, imho it doesn't get much better than this. Before I bought my AC5R I always somehow kept looking for my next guitar (even after a recent purchase), but since purchasing this one half a year ago I'm content (for life?). It may seem silly but everytime I pick it up I just feels such a joy playing, that I haven't experienced since I started playing guitar many years ago.
Sound is great, general feeling is great, build quality is great, and the SRT2 pickup system gives a warm plugged-in sound that typical piezo-only systems do not. I use it with the AER Compact 60 II amplifier myself, which is a very good fit for this guitar/pickup (along with vocals, if you'd like).
I own the similarly-priced Yamaha APX1200II with the SRT(1) pickup system, and they both yield similar (excellent) plugged-in sound, but the AC5R naturally has a wider unplugged sound, and it's my goto guitar for unplugged performances. I also feel that the general build quality of AC5R (Japan built) is superior to that of my APX1200II (China built).
It would finally be interesting to compare the AC5R with the corresponding model from the FG / FS Red Label series, say FSX5. I'm yet to try out the Atmosfeel pickup system (SRT is so good; can it even be further improved?).