If you're interested in upgrading, you got so many options to go with it's sick. Finding something that will improve upon the Bose AM-5 series 1 will not be difficult. It's up to you as to how much of an upgrade you're interested in, what your budget is, and what you want your system to do for you. For one thing, in 1987 all of your sources were still two-channel, now you got full range discrete surround sound, something that in 87 you could only experience if you lived close to select showcase movie theaters.

I would go to some specialty audio stores (which is where the Mordant Short types of speakers would be sold) and do some listening. If you go home and can still live with the AM-5s, then you should keep them. But, if your first instinct is to toss them, they by all means do.