Here are some of my experiences, but please don't rely on just one opinion (mine)....continue to solicit others for their opinions as well.

I would suggest that DSTAR is probably more in use (because it's been around longer), followed by DMR and then Fusion....in that order.

At one time I had a radio for each of these modes. Personally I found I like the audio quality best from Fusion (which is a form of C4FM digital). However, although there are a lot of Fusion capable repeaters in town (some  are set to digital/analog auto).....I didn't hear too many people actually making use of it.

DMR is an interesting concept, but in the end it just wasn't for me, plus...(to the best of my knowledge) there is only one DMR repeater in town (nose hill on 444.000) and I found some difficulties on using it depending on which talkgroups were active on it when I wanted to use it.

As far as DSTAR is concerned, I did far more listening on it than transmitting. But there are at least 2-3 systems in the Calgary metro area with various levels of use. Most are located in Calgary...but I guess coverage area could be a concern....especially with the effectiveness of DSTAR's error correction.

I should also mention here that there are some repeaters in the Calgary area which utilize APCO P25 digital as well. But I know-not of any amateur specific radios for this.....most users of those systems use repurposed/reprogrammed commercial radios in the amateur bands for use on those repeaters.

I currently do not own any digital voice capable radios...not because I don't like them....but I guess I don't like how it "locks me" into a particular mode/system/repeater. When one contemplates a purchase of these radios you really have to start thinking about who you talk to and what their digital capabilities are....  Realistically, analog is still the truly universal choice....which is why I enjoy it. I do realize that many of these "digital" radios are dual digital/analog....but I guess that's not "good enough" for my purposes.

That is why I have been interested in something called the dv4 mobile radio which is supposed to be a tri-band 2m/220/440  multi-mode digital (C4FM, D-Star, DMRplus, dPMR, P25 (NXDN later via software update) Voice over LTE and of course, FM)  "do-it-all" radio. But this has not yet materialized and after 2 years of talking about it....I question whether it will become a reality. (Plus it's sure to be expensive).

You also touched upon the Kenwood TM-D710 radio.....but to be fair this is not "digital voice" .... it is digital data/packet primarily for APRS. Yes, I have one of these radios.....I love it. Does everything I want....of course it's analog only for voice communications. However, note that Kenwood recently released a hand-held radio (the TH-D74A)  which combines an APRS handheld with a DSTAR capable radio..... There is much speculation that Kenwood will update the TM-D710 mobile radio with a successor which will also combine APRS and DSTAR.... but nothing definitive has been seen about this..... This Kenwood TH-D74A handheld retails for $899.99...if Kenwood releases a similar mobile...it's likely to be pricier yet.

Good luck with whatever direction you proceed.

73, de Tino, VE6MB