OP here, just back from the mainland & updating in case others are thinking about making the journey.
First off, it was a really easy and enjoyable trip. The food was incredible, and the speed with which you can get around is fantastic. This was my 3rd trip to China, the first in 1990 and the second in 2008. Since then the country has literally exploded with excellent infrastructure and technology; also the people are noticeably different culturally now, i.e. flattened by the internet (like everywhere).
Food was cheap, as were hotels and high speed train tickets. Second class train tickets were about $12 for a 2-3 hour journey and were totally comfortable. First class were double the price and somewhat better for longer trips (as long as I got the window or aisle in 2nd). I took business class once due to the others being sold out, and it cost $33 for an hour ride but was definitely not a 3x experience over first (they brought slippers and some junk food in a box). I took the advice Marko and others gave me and stayed at the Sofitel for a couple nights for $150/night, and also had a 5-star lunch at the Four Seasons in Hangzhou for under $100. Both were amazing deals. Most other hotels were $40-60/night and all very nice, comparable or better than a $2-300/night room in the US, and they all included (good, healthy) breakfast. My last 2 nights in Shanghai were another splurge for $200 in a very nice business hotel close to the airport and train station, which made for a convenient day trip to Hangzhou and easy access to my morning flight out. Defiantly worth it.
My full route went from Shanghai to Zhangjiajie National Park (extraordinary), then Guiyang and three "minority villages" in Guizhou province, on to Chongqing and Chengdu, then to Xining where I caught the overnight train to Lhasa for a week long tour, then back to Shanghai/Hangzhou before heading home. I haven't calculated how many miles all that was, but it was a lot! China is huge and I spent a good amount of time on trains & planes to get all that way.
Tibet was the most interesting part of the trip culturally, as it's still developing and has a rich Buddhist tradition that is still palpable. There is some very old remnants of architecture and art, but the majority of the places I saw have had to be rebuilt, but done well I guess (not having seen the originals). Tibetan food was the least interesting on this trip, but not terrible. Yak is lean and actually pretty tasty, like buffalo. I didn't much like the savory breakfast tea. The landscapes are really wonderful, and the sky a gorgeous, bright blue when the sun's out.
I can't say I'd go back to China in July since the weather was brutally hot in most places. My biggest complaint beyond summer heat was the sheer number of people and crowds. But what did I expect with over a billion inhabitants?? I was greeted warmly by virtually everyone, and even in a city as big as Shanghai people were friendly and very helpful. I had zero incidences of negativity from anyone, more often I was asked to pose for a photo with strangers for (their) fun.
The WeChat/Alipay issue was never resolved because I don't have a Chinese bank account, so everything except high end hotels had to be paid in cash. Generally that wasn't an issue, except in a couple taxis where--luckily--I had exact change. ATM's were not that convenient since all but Bank of China rejected my card. So that took a little planning ahead, but was manageable. T-mobile linked right up with the local carrier, and there's Wifi everywhere, so communication back home was no issue. iMessage worked great, but Apple Maps only sort of worked--mainly because the data over cellular wasn't great. I had a VPN and used it sometimes, but could often access US sites without it. I'd still suggest having VPN, however, as I did need it a few times.
Any concerns I had about the authoritarian issue quickly vanished once I got through immigration. As a city Shanghai is about as "American" as you can get in terms of rampant consumerism, shopping malls, luxury brands, fancy coffee, etc. The rest of the country (except Tibet) was mostly the same from what I saw. If anything, my impression was "we've already won the war" on the hearts & minds. Obviously things can change in a heartbeat and the CCP is real, but at the moment the culture there is very much the same as the rest of the world, i.e. all about consumption! In speaking to people, they have all the same average daily concerns everyone else generally has as well, so other than the food & language and some fringe cultural differences, I felt I could be just about anywhere on the planet.
Despite that, there is some heightened security. The tour in Tibet was officially necessary and going there required a special permit, arranged by the tour company. My traveling companion was questioned when she entered China, as per a couple comments in this thread. They basically wanted to to know where she was going, why she came, etc, but after that interview nothing. I once went to the UK for work and received a far harsher grilling. I personally had zero contact with anyone in charge in China, and the police I did see were pretty friendly. I did have to show my passport every time I get on/off a train or cross county/municipal lines with the Tibet tour, and there were a lot of cameras everywhere. I also noticed a lot of cameras on the roads where they photograph cars coming & going, so yes a fair amount of surveillance. But when I came back to the US I found that border control no longer even looks at passports now and has switched entirely to facial recognition, so I'm not sure we're doing any better in terms of privacy these days. Generally I felt very safe there.
If anyone is considering a trip there, I'd encourage you to go for it. It's a fascinating country and the food alone is worth the long flight! Any questions feel free to reach out.
