This is your own choice really. To what you have plan for yourself.

You pay cash for car, no need to worry later days you don't have money to pay back. And for the moment, you have nothing to invest in.

You pay some cash for the car, and invest in other things.

What I do is, I pay 10% for the car. I put the rest in investment. And I settle the car loan in 2~3 years time. That is what I did. Because for me, I need cash in hand for investment and business.

For you it might be different case.

Conclusion:
a) if TS money lying around in the bank or under his pillow, he can opt to buy CASH.

b) if TS has other place to put his money such as paper assets, properties etc, then its not very wise to buy CASH. Unless, the his investment does not need the the extra CASH.

Still, its personal choice.

I agree with @yhtan. @Squarepilot, if I've declare my income (say RM 1mil) , I can buy any items with CASH (say items costing around RM 100k) anytime without LHDN coming knocking at my doors. Unless I declare my income (say RM 100k), and buying CASH (say items costing around RM 100k), then I will have problem with LHDN.