Mike, I very recently had the same experience as you. Bought LR5 several years ago and when considering an upgrade the idea of a subscription plan just ticked me off to no end. I looked at many other options and tried a couple of trial downloads and decided that since I was familiar at least for the last ten years, with LR...maybe I should look into it further. So after buying a copy of Victoria's book and seeing the many improvements over LR5, I decided to go with the Photography Plan 20GB.
That was over the weekend and I've only used it for a day or so. Installation was uneventful in a good way, it found my existing catalog and photos(a concern if I'd gone with something else). It seems easier to import images directly from SD card and automatically eject(unmount) when done. Masking for localized edits is great and seamlessly moving an image to Photoshop(which is included with the plan) and back into LR...I'm impressed. Of course it could be that I'm also a luddite retired automation systems engineer and it takes little to impress me.
One concern that I believe was brought up earlier, the first thing installed is called Creative Cloud, which had me thinking something bad wrong with this. It wasn't, CC only handles the download and install of LRC and in my case Ps.
I was hesitant and a bit angry prior to playing with this new toy, but it seems to be a good value for $120/yr.