I missed that small detail, since the rest of the specs are the same! (The preconfigured R7 model has Win 10 Pro by default.)
I bought a R7 so I'll say it's worth it. But my reason for choosing the R7 is only because of the 32GB RAM upgrade option - it is not available for the R5. I try to keep my laptops for 5y or more, and given that the RAM is soldered, I went with 32GB RAM.
Thermally, it's said on reviews and on Reddit that due to the limited thermal management in the slim T14s, the R5 could be the more cost-efficient purchase as there is more room for chips to heat up. If thermals are a concern for you, the T14 (non-s) has better thermal management due to there being more space for air and a second heat pipe. The second heat pipe is subjective though, as comparisons between 2 generations of X1c with single vs dual heat pipe don't really yield significant differences. The heat pipe on the T14s is thicker than that on the T14, so there's something to be said for more material aiding cooling as well.
In terms of benchmarks, the gains aren't fantastic also. See notebookcheck for a comparison between the two:
https://www.notebookcheck.net/R5-PRO-4650U-vs-R7-PRO-4750U_12193_12191.247596.0.html
I think the battery life on the R5 is better than the R7.
Hence if you do not need the R7 specifically (eg, for the larger RAM options), the R5 is more than adequate. It still outperforms the Intel i7 variant, which says a lot for Zen 2 vs Intel's offerings.
My own opinion: If I didn't need 32GB, I would've stuck with R5. I wouldn't CTO just for a single processor change cos it isn't worth it imo. You can also buy 512GB NVMes that are better performing for around $100 or less now (check Amazon/Shopee) so Lenovo's $90 asking price for replacing is a bit much imo; and my experience with the default Kioxia that came with my T14s has been very poor - glad I upgraded it to a Samsung 970 Plus instead.
