The R8 is a very nice little camera and it's biggest advantages over the R would include;
- Size & weight - significantly lighter especially. You may not need the Fuji.
- Better AF, the excellent subject & eye detection may be a nice benefit to shooting young kids.
- Faster burst speeds (up to 40fps), which may be of some use if young kids are moving around quickly.
- Generally more responsive newer Digic X.
- As mentioned above, the R8 sensor has improved DR (so more latitude for correctly exposures of lifting shadows). It also performs well in low light.
Possibly the biggest downside might be the smaller battery and the need to buy new spare batteries, although the LP-E17 batteries are significantly cheaper than LP-E6NH. My R8 is fairly new, but I really haven't found the battery life too bad at all. It is FAR better than the pathetic spec result suggests.
Thanks a lot, I think you're right, wouldn't need my fuji anymore. Even if that piece of equipment is a real joy to use, despite a so so AF.
What do you think about the viewfinder of the R8?
I recently changed from a 6D ii + EF lenses & M5 + EF-M lenses to a R8, R10 + RF lenses, so I had a FF OVF and earlier (but decent EVF) on the M5.
Technically the R8 & R10 EVFs are slightly different - I think the actual "screen" is the same, but the magnification is slightly different.
The bigger difference is the rear LCD where the R8 has a 1.62 million dot screen and the R10 has a 1.04 million dot screen. I have not compared them side-by-side, but I can't say that I have noticed a difference between them in normal use. Perhaps if I was pixel peeping shots (playback) at maximum magnification I might notice, but I don't typically do that.
I am quite happy with both / either of them. I can see everything I want to see, including the histogram (I use "Small"). Now, I will say that I haven't used a R5 (or similar), so it may be a case of I don't know what I am missing out on.
My view is that the EVFs are perfectly adequate (but clearly not industry leading), and while you may notice a difference if comparing side-by-side, I do think that you would very quickly acclimatise to the R8 EVF and not notice that you may be "missing out". I think that some people tend to read too much into the spec differences and "think" that they can pick the differences in normal everyday usage - or maybe I just don't pay enough attention
I thought I might miss the bright FF OVF on my 6D ii, but I adapted to the R8/R10 EVFs very quickly. Yes, they are not as bright as the OVF, but they do show a lot more info, so it is swings & roundabouts (pros & cons). I really don't miss anything about the 6D ii (except maybe it's all-day / multi-day battery life) or the M5.
The R8 has a much deeper grip than RP (or any M camera), so it is perfectly usable with anything from a RF16 to RF 100-500L (I haven't tried anything bigger - well I supposed I have tried it with an adapted EF 100-400L ii which is bigger and heavier). I don't know what lenses you have/use, but I suspect the R8 would handle any of them.