Booting the diagnostic again confirmed the new chip type, higher internal clock speed and increased cache memory were identified correctly. Booting Linux showed a BogoMIPs rating increase of exactly four, from 16.59 with the original 33MHz 486 chip, to 66.36 for the 133MHz 586 chip, which is pretty much what you'd expect with a quadrupled clock. Perhaps the biggest perceived change was to the performance of xhosted applications. Netscape, always a CPU and memory hog, started up much faster, as did xterms, a clock and the other applications which I normally run. There isn't one.
Nothing needs to be recompiled or changed in any way.
There are no reliability issues. The fan on the Evergreen unit is completely inaudible when the covers are on the system. The only fault I have with the whole kit is that mysterious cache configuration jumper. It is clearly shown in the illustrations, but ignored in the body of the text. This lack of information on the cache configuration setting led to my trying out Evergreen's technical support by e-mail.