This type of price list is their reference for them to play their negotiation game. Now with internet, just type in a few strokes and you get some further details. As i mentioned earlier, go mudah.my website check. Those listing that the prices are lower are real, you can call to confirm and quite a number of forummers here did get deals as listed in the website.
Don't buta buta accept the price they give, don't need to give in to the pricing like on the spot (unless emergency lar), ask a few shops to compare, check website. If the pricing around 10%-15% difference from the lowest you seen, then you can consider the factor of convenience and familiarity.
And one more thing, ps4 is not known to be comfort/quiet tyre, although the performance is no doubt top notch. The best balance of price, performance and refinement now is the new falken fk510 in my opinion. Alternatively is the v12evo2 from hankook. If your budget is a little limited, please don't just solely think of the ps4 (despite prices are dropping) as these 2 listed are the best alternatives.
1 more thing i remembered, you mentioned about your brakes. Before sinking big money into a 4 pot set for the front, why not just get an upgraded brake pad a try, something like the the project mu bspec series :
http://www.project-mu.co.jp/en/products/pad_bspec.htmlHigher drag coefficient and temperature limit, means better bite and less fade.
A local seller you can enquire from :
https://www.mudah.my/Project+Mu+B+Spec+Perf...+c-61236332.htmbro, wanna ask your opinion as well, i got same car as TS too.
also cannot stand the road noise as using same setup as TS.