Re: Springfield Armory 6-20x56
They were originally made by Hakko and were VERY hit and miss in terms of quality/reliability. I have seen/used several different models of the SA scopes, including the 6-20x.
When you found a good one, they were decent scopes. However, they were often plagued with a range of problems. Some don't track well, the bubble levels on some tend to not be level, the glass is marginal at best (even for a $500 scope...some are just okay while others I have seen have a yellowish hue to them), the BDC reticles generally don't match up even with the prescribed ammo (168gr Match).
Last I heard, Springfield DOES honor the warranties on the scope. However, they don't do any work on them in the US, so they have to be sent to Japan for work. After months of waiting/wondering...you may get back a working, usable scope or you may end up right back where you started.
Greywolf said it well about being ahead of their time. The ideas were good...execution was less than good. If you can get one for a steal (<$300) then you can't go wrong since you can probably whore it out on eBay for twice what you paid for it. Otherwise...don't waste your time or your money!