Eliminating or reducing estrogen hampers some gains. Estrogen increases nutrient uptake, strength, GH and IGF-1 release, insulin sensitivity, RBC count, etc.....
Thats why the best gains are from Testosterone. Using an aromatase inhibitor (4-OHT is a metabolite of one) you eliminate some gains.
If you want more solid gains without water retention then its fine, but overall having some estrogen present helps.
Thats why I like M1T and 4AD. Best of both worlds.