I ask because all of the one's I've done the evaluation held their zero very well. So the setup testing course consisted of a timed run and gun course.
It is starts off with "back towards the range" start, turn and 2 shots @ a 25 yard target, sprint run to the 25 and a 2 kneeling shot at the 50 yard target, stand, and do a shoulder transition to shoot at the 167 yard target, do a shoot and move towards the 50 yard, and finally a 3 prone shot to the 167 yard target.
So here is the breakdown.
Pros: Selectable reticule, very rugged of all, well priced
Cons: Heavy for a RDS, Battery life, only 1/3 co-witness
Comments: I've had this RDS for a while now but on my test I approached this as a new sight to be compared. This thing is heavy when doing activities such as a run and gun maneuver. After 3 runs through the tac course the weight it added to my rifle felt like a brick. You sometimes have the tendency to look through this unit as if it is a scope which is not designed in the first place. Another is you loose peripheral vision around the sight due to its large scope like profile. Some of the good point were that it was more durable than the others and the reticule brightness was more pleasing on the eyes than the rest. I love the ability to change reticule to suit your needs to the type of environment you plan to use it such as a circle-dot for CQ, single dot for farther engagements. I would say that the Lucid HD7 would be great for more of a hunting/bench shooting activity with the occasional tactical carbine class use.
Aimpoint Micro T1
Pros: Lightweight, Very long battery life, slim tube design
Cons: Expensive, cap covers, bikini covers, only one mount which seems to be designed more for shotgun use.
Comments: Aimpoint has been considered the leader in RDS technology but it doesn't mean it is the best. It is expensive. I ran through the T1 with the same tactical course three times just like all the rest and this products keep me in check on my surrounding targets with its slim body design and this was the only sight that gave me the best, tightest group out of the rest. If you have read about complaints about the T1 being a 4 MOA rest assured that if decrease the intensity you can get close to a 2 MOA dot while still able to see it during a bright sunny day. The issues I had with the T1 is that they are expensive compared to the rest I mean it is more than double the price and honestly feel it is over priced for what you get. Another issue I had with the T1 are those proprietary adjuster covers. You lose them you can't adjust the sight. I guess Aimpoint relies that you would do a Ron Popiel and "set it and forget it" once you'd done with sighting. I would recommend the T1 if 1) money is no object, 2) do three or more tactical training courses a year to justify the cost, 3) you want the cool factor. I personally would not use the T1 for hunting. Though you could but the for that price point there are other better choices.
Pros: Well Priced, light weight, multiple mounting options, NV (Night Vision) option comes standard, cabled cap covers
Cons: NV button, bulky left control panel, bikini caps
Comments: First off all of the products that I tested are very durable and held their zero very well. I looked at the Sparc with the expectation that it would holds and built as well as the others and like the AR15 thread on the torture test of the Sparc it does perform very well. The ability to make the choice of either mounting the unit for an absolute or 1/3 co-witness is a breeze and to add that the adjustment caps are tethered to the body is a great way not to loose those small caps. Looks like Vortex studied their Aimpoint T1 competition and did their homework very well at a great price point. The issues I had with the Sparc is the left mounted control console. It is bulky though it may not look it but once you do some RAG (run and gun) a few times and trying to do situational awareness while acquiring your target you loose about 1/4 of your field of view next to your primary target. In a more tactical term, if you are engaging a targets side by side you would loose track of the left target when you are aiming at your primary target. The best way I can describe it is a ghost-like effect on the adjacent target. Another issue I have with the Sparc when doing a RAG is for some reason the NV (Night Vision) button seems to get pressed by my MOLLE gear and when you try to acquire your target the red dot is no where to be seen. So the first reaction you do is move he gun around to find the reticule and when you realize that you can't find it you think 1) the unit is broken or out of battery or 2) the NV is engaged while during that time you loose your target or loose time if you are in a 3-gun challenge. Finally the Sparc also has the issue with the bikini caps just like the T1. There is nothing wrong with them except that they seem to be easy to be broken or loss. The good news to this is what the AR forum Sparc review has noted that to get a pair of Butler Creek #4 flip-up caps. I have this on the test and they work great but seem to move around when the unit gets warm under the sun. The Vortex Sparc is a great unit if you are on a budget for a RDS. It is durable enough for tactical course use but if you are planning to do more than two courses a year then I would advise to save up and go with the T1. For hunting and bench shooting the Sparc is great but you would not have the ability to choose your reticule like the Lucid, which is a very nice feature.
So I hope this has been informative for you to make a decision based on what you want out of an RDS. Let me know if you have any specific questions. Good Luck.