SureFire F26 or FM35 red filter

I just recently bought the SF G2X pro. And being a cadet in Army ROTC we occasionally need a source of red light - for night time land navigation. I haven't really been able to find much for either the F26 or FM35 red filters on the forum (at least not via search bar). I was curious to hear your thoughts of purchasing a red filter.

Are they worth the buy? I've read that some other SF filters don't lose as much spill, flood, or throw - but not sure about these two. And, should I get a red filter, are there any big differences between the F26 and FM35 that's worth the price difference? Or would it be better to just buy a red flashlight from the get go?

Thanks.

Quality of construction is the main difference: the F26 is a slip-on with a body of fairly soft plastic, the FM35 has a cam to lock it on to the light and uses higher quality materials, hence the higher price. Both have a flip-up feature but will add a bit of bulk to the business end of your light. The Surefire filters are a good quality optically with a reasonable deep red tinge (some other manufacturers' red filters are more orange than red).

If you can afford it a separate dedicated red led light is the way to go - it means carrying two lights, but to be honest, that's not much more hassle than carrying light plus filter. Or you could look at the A2L - red and white in one.

Used to have the above-mentioned FM35 -- it was pretty heavy duty, despite being plastic. No way that sucker was going to pop off unless you unlocked it first. Once nice feature is that the filter lens folds back when opened, out of the way.

Yeah, I was taking another look at it earlier. Seems like the locking feature is a really nice perk to have, compared to the F26. Glad to hear reaffirmations of the filter not being able to easily come off as some other filters do.

Will have to go hunting for an FM35 then! Thanks all!