Yes you are right about the smt mics being difficult to handle, but with a magnifying glass and some patience it can be done.
There are a couple of reasons the mems are more attractive than electret imo;
1- price, I have bought 100 pcs knowles ellen mics, costs 71 cents/ piece
2- size, far far smaller than a 1/4 capsule
3- consistency, +-1dB sensitivity spec (verified by me)
4- basically class1 freq resonse ( altough i do plan to cal every mic in the array for +-0.1dB , +- 0.5deg
5- response goes up to 40khz easily, so phase info is good at 20khz
6- durabillity, the new coming infineon model is ip58(a meter under water!), and can withstand 1000g(!) Try that with your electret ( accidentally drop is or bounce into it, whoops there goes your diaphragm..)
7- ease of backend; differential output, so direct in to a line input of a decent ad covertor, no ultra high impedance ( and thus very sensitive for noise) circuity nessecary) input inpedance must be >=10kohm though, so no mic pre ( which is usually 6k8 or 3k4 because of phantom power load resistors)
I have a lot of experience with electrets and real condensers; mems makes me happy
I am pretty confident that electrets will slowly fade out, mems is just so much better, there are slowly emergibg class one spl meters, the only reason why there isnt a real class compliant spl meter available is because the iec/ansi standard demands electrical signal inserted directly on the preamp with a dummy capacative load, which cannot be done with a mems, so the standards need to be updated.
The thing with mems; you need more sensitivity/ lower noisefloor? -> just add more mics in parallel.
I have made an environmental sound measure station with 4 mems mics in the tip of a 1/2inch mic; 2 in parallel en 2 channels so you can verify the performance easily ( is there a difference between the channels?). This is something you just cannot do with electrets because its too large an too expensive
Of course putting it on a pcb would be the best solution, I fully agree, but for now we dont no what tthe best config would be and I want to be able to play aroud with it ( maybe make a square array or whatever I come up with in the future)
Also; making pcbs is ( big) money-out-of-pocket,
Something I want to minimize at the moment ( thankyou, covid)
Once we have a finalized design for the array we can do a group buy for a pcb version ( and then have some preamplification, psu and maybe even ad-> dante or usb onboard, that would be awesome