The Grade Alpha or Select Grade Alpha or Select Alpha Grade B all refer to the quality of the image. Select Alpha will produce the highest quality images without many artifacts or other disturbances in the image. For a little less money, the Select Alpha Grade B will give you the overall quality produced from a Select Alpah tube, but you will have some artifacts in the produced image. As for Gen 2+, this is about as close to Gen 3 as you can get, but at a reduced price. IMO, the images produced by Gen 3 are far superior to anything you will find in Gen 2 or Gen 2+. However, it depends on your usage. I personally have a PVS-14 Select Alpha Gen 3 system and I love it. It is handheld, lightweight, helmet mountable and weapons mountable (with optional mount). Would a Gen 2+ suit my usage, yes it would... but at the time I acquired one the difference in quality of images sold me on the Gen 3.
I think the best question is what would your budget and quality requirements be. Go with a MINI-14 or PVS-14 for the lightest weight and best performance. Both have weapons mount options and will provide good weather resistance.
We are currently adding Night Vision to our store selection and have access to all of these products. Many of them are already online, but I can assist you further and provide you with some images through different models, just send me an email.
