Metro has a very decent salary schedule. I can not cite specifics. One thing to consider in choosing a job such as you are thinking about. The smaller the dept. the less opportunity for advancement. Clark County is growing by leaps and bounds. They need to hire people to serve this growing public. However, not all the communities in Clark County are growing at the same rate. This also applies to overtime. The more people the dept employs, the more people off sick, on vacation or whatever. So, they need people to fill in for them. Then you get into budgets the dept with the biggest budget has the money to hire officers, pay overtime, pay benefits etc. Then of course there is the overtime for events. All the action is with Metro. If there was an economic downturn, the bigger department has the money to weather the storm.
I don't know how federal agencies work things, but I seriously doubt that they have a union. Metro has a union. This is a good thing. Instead of being on a payscale where you are a GS-? you have collective bargining rights with a new contract negotiated every three years.
I am not a cop, nor do I play one on TV. However I am a public employee who works on a daily basis with Metro. I am a firefighter with Clark County. I have a pretty good insight into the basics of the thing but I don't know the intimate details. I know the differences between our dept and that of NLV, Henderson and the city of Las Vegas. I have some idea of Metro's contract because our union and their union negotiate based on what each other got in their contract..............
I can tell you that the big department will get the better pay, better equipment, better chance of advancement, bigger and stronger union. They will hire more people meaning you gain senority at a faster rate.................. etc. This all eventually translates into a better pension. Do yourself a favor. Go for the varsity team.