No issues with temp and battery drain when I was using it but I can’t check it out further as it’s now seconded “temporarily” to my S.O and she likes it too much to give it back, dang. LOL! But I guess it really depends on what you do.
I’d say go for the 256GB, they don’t cost a whole lot more and you get more bang for your buck in terms of speed and storage. My Kingspec 256GB on Crystal Mark 6.0, YMMV. Speeds would probably lower for the 128GB.
KingSpec 256gb link
Seq Q32T1: Read 529.0 MB/s, Write 474.3 MB/s
4KiB Q8T8: Read 244.3 MB/s, Write 204.1 MB/s
4KiB Q32T1: Read 96.13 MB/s, Write 81.52 MB/s
4KiB Q1T1: Read 13.49 MB/s, Write 52 MB/s