That depends on your existing skills & career goals. The fact that 450 is being retired this summer will not make it worthless. The skills you learn while studying it will still be useful and if you pass you can still list it on your resume as an exam you passed.

My concern is that if you don't successfully pass it by the retirement date then the money spent on exam specific training or unsucessful test attempts may feel wasted if you'll never get to say you passed it.