These are the numbers I measured on both cams:

MM305 S: 305º/320º@.020", 279º/287º@.050", 197º/200º@.200", 143º/143º@.300", 112º/107º@.350", 0.433"/0.420"
324/324: 324º/324º@.020", 290º/290º@.050", 200º/200º@.200", 145º/145º@.300", 112º/112º@.350", 0.433"/0.433"

The new MM305 S cam has a more aggressive intake lobe, with less duration at 0.050" but the about the same at 0.200" lobe lift.
The exhaust lobe is not as aggressive as the intake, very similar to the old 324/324; perhaps more stable from a valve float perspective.

Any one have a sound clip of the 324 at idle ?

I don't have a sound clip but I can still remember from all those years ago when idling waiting to enter the water box@900rpm on my all iron 446ci, you could almost count the cylinders as they were firing, that motor made 529fwhp with that cam and it was only around 9.8:1 with nothing special BV 906 heads with a stock 440+6 bottom end and a crappy team G and an 850DP, best part in that motor were the HS roller rockers....

As best as I can remember from listening to the BB Duster parked next to me in the pits one day: "RUMPity... RUMPity... RUMPity..."

This cam was designed for big motors with crap heads. I had a 535 with 906 heads on it. About a perfect match.. stall it to 5,000, shift at 6000, maybe shorter . I would like to know what the running duration AT THE VALVE is at full lash. I bet it is a ton shorter than a guy would think.

I’ve never used one........ and I can’t imagine actually building something with the parts that are easily accessible these days, where that would end up being my cam of choice.

My understanding is they were designed at the request of Herb McCandless specifically for high CR bracket race 440’s with ported stock heads for guys who didn’t want the expense of a roller cam.
(I see this thread in ancient....... and that this was already mentioned years ago).

They’re probably fairly well suited towards anything in that vein, as in....... high compression, race only, small heads.

Yeah I'm actually old enough to have talked to McCandless about this cam sometime back in the 80's or early 90's. I don't think I ever bought one from him but I might of. I did buy a few of the mushroom tappet cams from Herb. He didn't want to sell those mushroom tappet cams to me. Said they weren't any good and told me to buy the 324/650 instead. I was building a "high tech" stroker engine using a welded crank with 383 rods and ported 906 heads. That was the good stuff back then. After I finished up that project Mopar came out with the Stage VI head and that was the writing on the wall for the big flat tappet cams.