To be fair, with Contiki, a Commodore 64 is also usable for checking email, word processing, telnet to a Unix server (if you don't really need 80 columns), and games, even though it's much slower than the Model 30 or Model 25 and has less RAM.
These particular PS/2 Model 25's probably had an edge on the C64, though. Having proper Ethernet cards and access to Netware servers allowed loading applications a lot faster than, say, a 1541 disk drive. Although my present-day C64 with Ethernet adapter, SD2IEC, etc., might could give it a run for its money. :)