The key factors when comparing deca vs d bol is the benefits vs rewards. Always you have to consider whether you need slow-acting or fast-acting and how they will fit into your cycle. If you already have a stack set up, take into account any interactions that might occur. For a quick recap on the comparison, Deca Durabolin is slow-acting with added medical benefits while Dianabol is fact-acting with more severe side effects. Using them in combination is very common and can increase the effectiveness of both of the products. As with any new cycle, keep an eye out for any problems or lasting side effects. Contact your coach or doctor if you feel something is impacting your body or performance.