I have a M11 radio with a Spektrum module and I need some advice on if it's worth upgrading to a newer radio like the Futaba 4PKS-R. I mostly use the M11 for racing at club races and most of the time it works fine except for some bad glitching from time to time during the mains. Would I notice a big difference with a new Futaba 4PKS-R or the cheaper 4PLS?

Try the Sanwa MT4 it has telem as well but also runs at the higher frame rate like the 4pks-r / M12 etc and is far better built than the 4pl IMO

there is a noticable difference in speed between the 4pksr to the 4pl......

I'll have to take a look at the MT-4. It's been a long time since I bought a radio so I'm a bit behind on what's new. If the 4PKSR is noticeably faster than the 4PL then it's safe to assume it's faster than my M11. But i'm curious if I'll even notice the difference between that and the M11 because I don't notice any lag or delay during racing other than some glitching I sometimes get which I did not think was possible on 2.4GHz.

If your a serious racer and you are looking for any advantage you can get, upgrading to a high end remote I.e. the fast latency model remotes, you will definitely notice a difference. You don't notice lag until you get something faster..... For the money the MT4 is the best bang, but I still prefer the ergonomics of Futaba remotes.

Thanks for your advice. I've never held the MT4 yet but I really like how the 4PKS-R feels in my hands. So I'll have to try out the MT4 before I can make a decision and hopefully it will feels just as comfortable as the Futaba.