What would the purpose be, to boost test levels?
Clomid should not really be used long term as it can affect your eyesight, you should get a PDR (pocket drugbook guide), Nolvadex can do the same but since its used in lower doses (and pwerhaps other reasons) it does not have this kind of problem.
Moreover you do NOT want to F#CK with your estrogen levels on a long term basis, for MANY reasons.