Not exactly the same, but this is my thoughts, without checking out the Scan Tron 250's before typing. You have one being a single mirror, while the other being a barrel mirror that tosses light off the sides and up as well as down. Not exactly a fair comparison of the two fixures you selected.
I have the Electra. My only complaint is that it really is not bright enough. That's why there's the Electra 250, which I am considering. Simple, single place the projected light goes(based on the mirror). Well, I needed to throw more light around, so I got the Rover II. Basically an Electra with a barrel mirror.
Well, needing to kick it up, I got a Reflex, which is two independent Electra's, and a Barrel Flex, which is two independent Rover II's.
Now, none of these fixtures are as bright as I would like them, but my audiences seem to enjoy them. I think they are neat too. But, I have to hang 4 fixured to do what want, although with all 4 going, it's low draw and lots of movement.
This goes to what Jingles said, and the direction I am going.
Buying a more flexible and capable fixture that can do a few more tricks does cost more, but in the long term, you save. Why? Less fixtures. Drawback: sometimes you may have to give up something, then again, maybe you don't or it doesn't matter for you.
By getting a more feature packed light, you also save on weight, current draw, and fixtures you have to hang. This means less fuel consumption, less chances of popping a circuit and quicker set-up and tear-down time. This all equates to more money in your pocket at the end of the night, season or year, depending on how you do your accounting.
Back to my situation, budgettng only permitted me to buy less expensive fixtures, but at the same time, kept my audiences entertained and continued to keep me light-years ahead of my competition. My competition: two square trusses vertically floor mounted with 8 Par64's(4 on each truss) running off a program in the dimmer pack. Yeah, reall snazzy. You can visit my web site and see my inventory so you know what I'm talking about as far as what I own. A nice feature about some of the fixtures I have is the "sound activated" takes a lot of work off me by letting the fixture bounce to the music. Let me say that despite the functionality of DMX, some of these fixtures will definately stay in my active rig.
Now that I know more, my focus has changed a bit. Intel lights and better capable lights are the way to go for me. Fewer fixures with more options. Why hang 3-4 Par38's when I can hang a single Par64 LED and get all the same functionality with fewer fixures, plus more light and less heat and less current draw.
Back to your situation: You're dealing with inexpensive solutions that will get the job done. That's good. Notice I am not saying cheap. Jingle's throws out a set with DMX, which will of course throw the price way up, but then you get control. You're probably also getting a better fixture as well since it appears that when you have to spend that extra money, the companies build their product better.
Your choice. If it was me, I'd have a hard time deciding, but I think I'd save up and go for the ScanTron 250-type fixtures. Why? Now that it has been brought up, that's the next type of fixture I am looking at getting.