I have one of these myself, and it still works fine, so I'd expect this one to still work as well.
Please note that this card NEEDS an 8 bit slot, although a 16 bit slot will work as well but might have some problems. Needs ISA slots, not the newer PCI slots. So MUST have older computer.
The reason for the interest in this card is the interest in playing the older computer games. Some of these were designed to use the Roland MT-32 sound module, or the compatible CM-32L box. The LAPC-I (as noted, this is I as in IBM, not 1 as in 100) is an on-card version of the CM-32L, with a midi interface as well. Many of the games that used these devices needed special sounds creating, incl sound effects, and these could be programmed into the device. Playing the games with the original/proper sounds is much appreciated by the fans of this sort of thing, there are web sites devoted to this side of things as much as the actual games. Look up about the MT-32 as much as the LAPC-I card.
So, the interest will come and go in step with the interest in the games that use it. As with the prices that might be paid.
There are now emulators (look up the MUNT project), also modern sound modules may have a CM-32 mode (or just C/M) which has the MT-32 sounds (but I understand NOT the ability to load the special sounds as the real devices can do). So you are looking for an increasingly specialist buyer, BUT, those are the sort of people who may pay the better price.
Geoff