Smarty is faster, if that matters. Conclude by viewing this comparison . Of course I know how to look at these tests as something limited. The test is valid for these conditions. Something different may happen in your circumstances. It depends on the environment, the code, the practices adopted. I do not even know if the person who performed these tests knows how to use both correctly and is interested in disclosing unfavorable data to their preferred mechanism.
So install both, learn to use them, do what you need in both the best way you can and measure performance. This is the only result you can trust.
You are probably asking other people to take the test for you because, even unknowingly, you know you do not pay for the test, the difference will be minimal, especially because you are already using a performance-less language. If one were so much faster than another and that was important, the slow if it were not dead, at least it would be considered by the whole community as something unfeasible for those who want performance. And this is far from true.
Another important thing. If you need performance do not use any of them because they both add runtime bringing results that many question. Use one of them or something that makes your job easier for ease, not performance.