I know nothing about DHB. Deca is a tried and proven bulking steroid with a very long history. MENT is relatively new with very little ancedotal evidence and even less scientific evidence to lean on.
MENT will not cause deca dick or a decrease in libido. It is the only steroid in existence that will maintain all male sexual behavior in the absence of testosterone. When using MENT my libido skyrockets and I get wood when the wind blows. The only negatives for me is oily skin and quick conversion to estrogen.
Deca I experience a loss of libido and struggle getting solid wood about 6-8 weeks in. I have had very few pimples in my life but when I use deca I get a few here and there.
If I was in your position and wanted a solid straight bulking cycle I would go Test/Deca/Dbol. With good clean calories and a solid training regimen this never fails to add mass.