Just a comment about any warranty - it is much better to never need to use it.
Last summer at NSCC, a new scope (not a FM) fogged up. It did get soaked in the rain. It was replaced under warranty in only two days, the replacement being sent directly to the DCRA office at Connaught. But two days in the middle of national level matches is a loooong time.
Doesn't matter how good a warranty is, it is better to have a scope that doesn't fail.
There have been a number of reports of FM failures here at CGN, the reports coming from credible individuals.
At my shop, I used to sell some bargain priced scopes. Few failed in use. The distributor was very good about replacing them. Stop and think about it - often a no questions asked replacement policy just means that the things are so inexpensive to the distributor that they can afford to write off a percentage, and not even bother with repairs.