Whos the best?

I like the arm on the bottom one and the refactor on the to one.

I like the one on the bottom too.

In my Opinion, I think GE makes some of the highest quality NEMA'S and they have made real innovations in lighting for years. For one, they were the first to design a reflector latching system on the true NEMA fixtures. Other manufacturers followed suit after that. The NEMA latching system goes back to around 1941. They seem to still make quality street and security lighting today. You have to go through a business or electrical supplier for any true NEMA fixtures today. Don't get me wrong, but ITT made a good product too, but I believe GE made some of the longest lasting and most durable security lighting for decades, ditto for the GE ballasts, too. I have a GE SA-201 HPS and a MV version of that fixture on the way. I have a couple of Powrbrackets, too. 

............by the way, I like GE NEMA's the best to, for the wide variety and quality of their bucket lens fixtures, too. I like the good ol' standard bucket shape but I think the tapered one is interesting too. There are many different refractor lenses that will fit on the GE NEMA heads.

GE. made some really good NEMA's in the 60's and 70's.. I have some modern GE "NEMA" type heads, 175 MV  from the mid 2000 era and they are not bad, at least they started using  a copper wound ballast.. One fixture that has gone to pot quality wise though is the Power bracket...I have an original first gen unit from 1963 except for the lamp, it is all original even the original Astrodome clear GE made pc is still wotking! The aluminum casting on my first gen is super heavy duty! There is enough true aluminum in this unit to make 5 modern thin cast weak pieces of S$^! I purchased 6 250 hps units a few years ago and was I surprised just how thin and flimsy the power bracket has become.. I installed them on a job and had to go back a few months later and replace a few refractors because the cheap engineers at GE lightened up so much on the casting thickness around the refractor "EARS" that once the latches were clamped down, there was not enough "MEAT" to hold the reflector to the head and the wind just loosened them up and down they came! I ended up using tie wire to attach the reflectors... Just too much garbage made today!

Wow! I didn't realize the Powrbracket goes that far back. I'm going to keep an eye out for one of the early ones then! I've heard about the built-in Astrodome PC.

I have 2 NOS Powrbrackets; one a 70W HPS, dated 1997 and a 400W Mercury vapor, dated 1995.; The quality on these seems pretty good, so maybe in the last 10 years, they started skimping a lot on the materials. The fixtures I have weigh around 20-21 lbs each. I think the reflectors are a little thinner aluminum than I would like, but these look pretty neat though. My Mercury vapor Powerbracket has the "flying saucer" shaped refractor/reflector.

I also have 2 NEMA SA-201's, one HPS, and one MV; these were both made in the 1990's.

Hello Blum...... yes the "Powr/Bracket" was introduced in 1963.. the early ones are AMAZING in quality...like a 60's american car........ built heavy and to last ( big V-8's and METAL BUMPERS! LOL)  
The Astrodome PE control was quite an innovation in the lighting market back then. I have a GE lighting catalog from 1964 and it is fun to look at the print that GE had touting the benefits of the "sleek design" of the "bump" on the streamlined fixture.. Your  400 watt unit has a "PA" optical assembly, the big saucer shaped reflector with the big tapered refractor.. The 250 watt HPS units I installed had these same reflector/refractor assemblies with the later "lightweight" latch assemblies that GE made from around 1978 on for the higher wattage units and not as stout as the earlier "compound spring" latches.. I will get some pic's of my early units and post.. The early 60's luminaires also were painted silver and not the latter grey.. I will bet my  early 175 mercs weigh in MORE than  a 2000's 400 watt design.... Take care..

I have a 2004 Cooper Vanguard III that I installed this year in a very windy location on a pole that tends to swing slightly in the wind. Seems of good quality, we'll see how long it lasts.

Both brands have been around a long time, and have a very good track record. Therefore I like them both.  However the GE refractory looks cooler 

In my opinion,Traditional nema heads are better than GE nema heads.