Which sensor type is more likely to go off for nuisance alarms: the ion or photo sensor type?
A main consideration is how to hardwire one of these if all you already have is a hardwired ceiling mounted light fixture right next to where you want to mount the smoke alarm, but nothing else - that is, not yet anyway. I am no pro contractor, but I could do it myself no problem. What do you need to do wrt making it look and function as legal and safe (as need be) by running directly off a nearby light fixture (with it's in ceiling wires)? String a wire, under the ceiling drywall or over, need to cut a oct box into the ceiling, hard-shield the wires, etc., what?
I bought a Kidde Pi9000CA dual sensor smoke alarm (ion & photo) that runs on a (std. alkaline) 9V battery only. It has HUSH and TEST buttons. I am not too concerned about not having either the interconnected (wireless) feature or the hardwired features simply because you cannot get it with both of these features at the same time; either is a bonus, but both is the only way to go.