@TNSTAAFL - I took a look at the manufacturer's specifications for the Vortex Crossfire II 2-7x32mm crossbow scope and compared them to the specs for the TenPoint EVO-X. If you're going to use the single pin sighting approach, I would keep looking for a better light-gathering scope that has a single crosshair instead of at multi-stadia reticle. If you're considering using the multi-stadia reticle as it is intended, then here's the rundown on the important specs to compare between the Vortex Crossfire II and the TenPoint EVO-X:
Main scope tube diameter:
Vortex = 30mm; TenPoint = 30mm (Identical)
Objective lense diameter:
Vortex = 32mm; TenPoint = 36mm (Advantage goes to TenPoint)
Parallax-free distance:
Vortex =75 yards; TenPoint = 50 yards (Advantage goes to TenPoint)
Approximate Magnification Power setting for 330 fps crossbow bolts:
Vortex = 3.0X; TenPoint = 2.5X (Advantage depends on personal preference - i.e., higher or lower mag preferred?)
Approximate Field of View at 100 yards at power setting for 330 fps crossbow bolts:
Vortex = 49.2 feet; TenPoint = 73.2 feet (Advantage goes to TenPoint - a pretty big advantage)
Approximate Ocular Lense Exit Pupil Diameter at power setting for 330 fps crossbow bolts:
Vortex = 13.7mm; TenPoint = 20mm (Advantage goes to TenPoint - a huge advantage for low-light performance)
Ok - so here's the breakdown of what the above comparisons mean in layman's terms...
Objective Lense: A larger objective lense gathers more light. The difference in objective lense diameter between these two scopes is not large - but it IS significant, because the larger the area of the objective lense, the more light it collects. The area of the TenPoint's objective lense is 27% larger than that of the Vortex's objective lense - that translates into 27% more light gathered to help you see in low light conditions.
Parallax: Parallax is the phenomenon where you have inaccuracy introduced due to misalignment of your eye and the axis you want to view. A good example is if you have ever been in the passenger seat of a car and you look over at the needle on a speedometer when the driver is at highway speed... it will seem to indicate a different reading than what the driver sees because of the offset between the plane of the needle and the plane of the lettering of the speedometer. The inaccuracy that you see as the passenger due to not looking down the axis of the speedometer is "parallax". A fixed focus scope is only parallax-free at one distance. At the parallax-free distance, if your eye isn't precisely aligned with the axis of the scope when you fire, it won't matter because the aiming error introduced will be exactly zero. The more that the shot distance departs from the parallax-free distance, the larger the aiming error when your eye isn't centered on axis of the scope. If your most probable shot distance hunting with your crossbow will be between 10 and 40 yards, having a scope that's parallax-free in the exact middle of those distances (25 yards) would be ideal. Note that the Vortex has a parallax-free distance of 75 yards (which is more suitable for a rifle than a crossbow), whereas the TenPoint has a parallax-free distance of 50 yards. Also note that the layout of the HC Mini makes it easy to have a certain amount of misalignment between your eye and the axis of the scope. (You have to tilt your head a little awkwardly when using the scope.) Advantage goes to the TenPoint.
Ocular lense exit pupil diameter: This is the diameter of the visible light transmitted out the back of the scope to your eye. The larger the exit pupil diameter, the brighter the image appears to you because you're getting more light into your eye. Note that there's a SIGNIFICANT difference in the exit pupil diameters of the Vortex vs. the TenPoint. If looking through scopes with equivalent objective lense size and glass quality, it's the circular area of the exit pupil that affects perceived brightness of the scope. The circular area of the exit pupil of the TenPoint is 113% larger than that of the Vortex.
Conclusion: the TenPoint objective lense collects 27% more light into the tube than the Vortex, and the TenPoint ocular lense emits 113% larger area of light to the viewer's eye. Vortex makes a decent product, and so does TenPoint. These two scopes aren't equals, however, so only you can decide if those differences are meaningful enough to you to justify the price difference. I hope I haven't caused confusion, and that this info is helpful to you. These numbers probably aren't real meaningful - I get that. But without trying both scopes side by side in low light, it's hard to know exactly how big of a difference in low light performance there is. Is that a possibility? Could you just buy both and (without mounting them) compare them side by side as it gets dark in your yard? Then return the one you don't want to keep?