Most in-service-inspection Engineers are MSOE MBES. They also register EngTech .
It is costly to be a member of more than one professional body, in my case the fore mentioned
was paid by employer, as it went to Taxman each year for benefit in kind, did not want to claim tax relief on MIET + EC registration. So would advise one or the other. MIMechE is highly regarded as is MIET, so you have a choice. Do not know about IMechE magazines. But SOE are very good for your class of work.