I have owned my Epiphone J-45 for almost two years now and am very pleased with the overall sound and playability of the guitar. The guitar has a well-rounded tone, especially bass and mid for playing rhythm, but sounding great on lead parts as well. I'm more interested in the acoustic sound of the guitar, as opposed to playing it through an amplifier, so I can't comment too much on the pickup and amplified sound other than it being an additional feature for those who might be interested in it.
Gibson guitars, and by extension Epiphone guitars, have somewhat of a reputation for spotty quality control, and unfortunately some of this can be found on the J-45 I received as well. While the overall guitar certainly looks very pretty, there are a few minor blemishes such as the rosette fading out a bit on one side. Additionally, there is a slight narrowing of the neck near the heel where it has apparently been over-sanded, though I found that this did not affect playability whatsoever. The pins are also set a bit deep in the bridge, making them hard to remove from the outside. Over time, the guitar developed a slight buzz on the bass strings which I haven't managed to resolve yet with a truss rod adjustment, so possibly the bridge might require a shim or some fret might be causing the issue. I accepted these faults when taking into account the quality of the guitar's sound and feel, but it is up to each individual buyer to decide whether they mind such quality control issues at this somewhat higher price point. Additionally, it would be appreciated if Epiphone included a gig bag at this price, if not a full-blown case, but you will unfortunately have to buy it separately if needed.
Adding on to the point of quality control, there is a definite variance between different guitars of this same Epiphone J-45 model. I managed to see and play a few of these guitars and noticed both noticeable differences in the neck profile as well as some slight tonal differences, so keep in mind that the J-45 you are playing might not be exactly the same as another J-45. It comes down to whether the particular guitar feels right for you.
To summarize, the Epiphone J-45 looks and sounds wonderful, but you might have to live with a few quality control issues. The price is a bit steeper compared to some competitors, but the sound and feel of the guitar are still punching above it's weight, therefore offering good overall value.