PSS: ultra super awesome dry grip and cornering
PS3: super dry grip, okay wet grip
ST3: super duper quiet
XM2: super fuel save, awesome thread life

I hope i summarize it quite correctly? Lols.

Yesterday went Glenmarrie Shah Alam replaced 4 pcs of XM2 size 185/60R15 for RM 225 per piece, with RM30 petrol voucher.

no i dunno the price.

if safety, i think PS3/ST3/XM2 all up to standard.  if prefer quiet and safety, the the obvious choice i think is ST3, since you mention you not a racer.  and the quietness comparison between all these tyres... well, i've no idea at all!  you have to ask a person who has actually used both ST3 & PS3, preferably on a same car before.

well, when comes to quietness and smoothness, since it is relatively new, of course it is much better than the stock tyres which were the Bridgestone. However, may be personal preferences, Michelin always my choice of tyre and i have been using different types of Michelin tyres in different cars such as xm1 (myvi and wira), XM2 (PC), PS3 (vios), Primacy LC (Camry and Prius) and Primacy 3ST (Camry). I can only compare with Bridgestones, Continental and Goodyear caz those were the stock tyres for some of the cars above. In term of performance (handling and gripping), continental was good on Camry but in term of quietness, smoothness and comfortable, Primacy LC and Primacy 3ST are much better, though Continental was much more expensive than Primacy 3ST (RM500/pc). PS3 were on vios before, in term of quietness, gripping and comfort, similar with Bridgestone stock tyres, just a bit more smoother and softer. XM1 & XM2, i feel that XM2 is much more quiet and gripper than XM1, and XM1 was relatively a bit more noisier. Primacy LC is much better than Bridgestone stock tyre on my Prius in term of everything, including quietness, softness, smoothness, gripping and comfort level.
Well, this is my personal preferences and opinion on Michelin tyres. TQ.

Hahahha, just a bit to share only bro. The Primacy 3ST I have got it replaced on my Camry before Raya, was done under to the Raya promotion, RM500 per piece, 215/50R17, nitrogen gas, balancing and alignment plus RM30 petrol voucher. Since the replacement, i had traveled about 700 km, from city drive to to coaster road, but still relatively new, can't tell much about it. However, my experience with 3ST can be considered as so far so good. In term of gripping, much better than Primacy LC. Better smoothness and quietness but rolling resistance, i think it is just normal as on the afternoon, i can feel the rolling resistance quite significantly, especially under the humid and hot afternoon.
I am not sure what type of expectation you would want for your car. Like me, caz i always travel long distance and i always put comfort and smoothness as priority, so 3ST will be good enough for me. But if you opted for performance and handling, may be PS3 will be much suitable for you if comfort isn't your priority. But this doesn't mean PS3 is not quiet or smooth, just their comfort, quiet and smoothness are at the normal level. I tried PS3 on vios before, i feel grippy and handling; better cornering and performance but it was quite bouncy and noisy. Well, nothing wrong with PS3, just individual preferences.