Templates vs CTFE

[Max Samukha]

Some of us who have the knack of writing metaprograms in D know that 
many algorithms can be implemented with both recursive templates and 
CTFE. A simple example is map:

Recursive template instantiation:

template staticMap(alias pred, A...)
{
     static if (A.length)
         alias TypeTuple!(pred!(A[0]), staticMap!(A[1..$])) staticMap;
}

CTFE:

template staticMap(alias pred, A)
{
     mixin("alias TypeTuple!(" ~ _staticMap(A.length) ~ ") staticMap;");
}

private string _staticMap(size_t len)
{
     string result;
     if (len)
     {
         result ~= "pred!(A[0])";
         for(size_t i = 1, i < len; ++i)
         {
             result ~= ", pred!(A[" ~ to!string(i) ~ "])";
         }
     }
     return result;
}

It is not easy to decide which approach to implement in a library 
because both have drawbacks.

Can anybody give informed advice as to which one is preferable in 
practice? Or should a library provide both?