250 watts seems a bit much for a residential area.

Well the AEL 327 is recommended for a residential area too so...

Yeah. AEL seems to practice the copy & paste method well.

I agree, this light is way too bright. The previous light was a 175w merc (with a very yellowed refractor). At least this fixture is FCO so it doesn't shine into the residents' homes too much.

Hmm. Here a 175w fixture would be replaced with a 100W HPS light. Here it seems to be this way:
100W MV --> 50W HPS
175W MV --> 100W HPS
400W MV --> 250W HPS
*1000W MV --> 400W HPS
*= was only used for floodlights; 1KW streetlights were never used here
Also, I have yet to see a 250W merc ever used here. I'm convinced they never were. There have also been occasions were 100W MV fixtures were replaced by 100W HPS and 400W mercs being replaced by 400W HPS, but that's not too common.

175 watt mercury vapor streetlights in my area are replaced with 100 watt high pressure sodium streetlights when they fail, they also replace 250 watt mercury vapor streetlights with 200 watt high pressure sodium streetlights which is odd, the replacement should only be 150 watt high pressure sodium for 250 watt mercury vapor.

West Penn Power:

175 watt MV - 100 watt HPS
250 watt MV - 200 watt HPS
400 watt MV - 200 or 400 watt HPS
1000 watt MV - 400 watt HPS

My area

100 watt MV -> 100 watt HPS
175 watt MV -> 150 watt HPS
250 watt MV -> 250 watt HPS
400 watt MV -> 400 watt HPS
1000 watt MV -> 1000 watt HPS..........

@Michael, yes RI had 1000w MV street lights. I recall seeing some M-1000s there, downtown Providence had some.

@ Dave; Ah. That must've been long gone before i was around then. I see M-1000 in parking lots. Some double-door OV-50 too that are in parking lots.
@ Jace; odd how they replace them with the same wattage. I guess it makes the the roads brighter though which can't really hurt too much...

My power company replaces fixtures on a watts per lumen basis.

Here too, but they round to the nearest lumen margin. They strictly install 50, 100, 250, and 400W HPS lighs here. That's it. IMO, there's too much of a lumen difference between 100 and 250 watts HPS. I also think 50W HPS is too dim especially if there's not a light on every pole.

Around here HPS replacement criteria seems to be totally random. I've seen 175w mercs replaced with 150 and 250w HPS. I think they replace them with whatever wattage they have on the truck that day.

I know over here it was like
100w MV to 70w HPS
175w MV to 100w HPS
250w MV to 100w or 200w HPS
400w MV to 200w or 250w HPS
1000w MV to 400w HPS (was only used on freeways to my knowledge)

Duquesne Light:

100 watt MV - 70 watt HPS
175 watt MV - 70, 100, or 150 watt HPS
250 watt MV - 150 watt HPS
400 watt MV - 250 or 400 watt HPS
1000 watt MV - not sure since they're not used on the roads in Duquesne Light's area.

I know my OV-10 (175W MV) was replaced by a 50W HPS Cooper OVZ. The OVZ died after a few days of service and was replaced by a 50W M-250R2. That's tha quality of Cooper in a nutshell.

Just Sayin