Welcome to the forums. Looking into radios you will find that there are so many more options now then there ever was, and asking advice on them is almost a mute subject jus because every ones various opinions are gonna be based on loyalty to a certain brand. Once one gets into a radio for the first time they usually stick with it and defend their choice from there on out. That being said most find that whatever system they go with is gonna suit their needs. Its like language, if you speak English and your friends and family speaks English then that's what you use. But that doesn't mean Spanish or French are inferior languages.
So here is what you may want to consider. Spektrum has been a staple in the RC community for quite a long time because they came out on the market with reasonably priced high quality radios that are user friendly. Plus they exploded onto the scene with grand marketing, and it is reflected in the price. This is what made them so popular, so you will have people that committed to them. And they are great systems, however if you choose Spektrum then YOU are committed to the DSMX protocol, and there is nothing wrong with that, as long as you are willing to do so. But if you are going into drones and quads which out of the box there is no guarantee that any off the shelf quad will run a DSMX receiver. So in turn you will have to dig into the quad to change the receiver, hope it fits and hooks up right. These receivers can be sourced and are used, but mostly if you plan to build your own quads. But you are still DSMX specific.
A multi-protocol radio that uses OpenTX will give you the options to just pull a quad of the shelf and bind right away with no mods to the electronics, whether it is a DSMX or any other protocol, albeit FrSky, FlySky, DSMX, or any other of the 40 or so protocols you will find with OpenTX. And another thing to consider is not all protocols perform the same, some are better for different reasons then others as well. This is something that I have done the research to some extent in given my experience and this is what I found. I started with Spektrum and had nothing but communication issues to begin with. And yes one phone call to Spektrum and they sent me a new radio free of charge, no shipping charges and I didn't even have to send the old one back. Their customer service is amazing, however now I have two radios that I cant use. Realistically if I had known then what I know now I wouldn't have gone with Spektrum to begin with. I feel I wasted the original money spent on the Spektrum which could have gone into the Radiomaster I own now. But in my plight I reached out to the forum community here and most of the Spektrum loyalists cursed me for switching saying they have never had a problem with theirs. Kinda made me feel like its something I was doing wrong. So I went to the local hobby shop, which are Spektrum dedicated and I got my original radio from and this is what I found.
At the store I had them take me through the whole trouble shooting process with me, and it ended up being a Radiomaster/Spektrum show down. I walked into the store with my Radiomaster TX16S and the first thing the clerk said even before I turned the radio on was that my radio was garbage and that was my problem. I told him that they sold me Spektrum and I had nothing but problems so I switched. So we went through the motions and put it up against the DX9 with Spektrum receivers in a range test, and the Radiomaster out performed the Spektrum, even with the Spektrum receivers. Even the clerk was surprised at what the results were, and he wasn't cursing the Radiomaster anymore. Now I have completely dropped DSMX and I have flawless communication with FlySky receivers on the TX16S. I still have the option to use DSMX but I don't see a reason unless I buy a plane or drone that is already equipped with such, then I will use it.
Take this however you like, and I don't mean to step on any ones Spektrum toes, and I will say they are great radios, but when it comes down to the options you get with OpenTX for the money, you will find that OpenTX has better value. The options are almost endless with OpenTX as long as you are willing to learn the language. And really there is so much info on YouTube on it that you will be finding new things you can do with this Radiomaster weekly. Sorry
@Bricks but it is what it is, no offense intended. For some reason this can be a delicate subject, ran into that a couple days ago on here. But this was my experience with it and I cant 100% back Spektrum. If I never used Spektrum before then I couldn't offer an opinion. But I have and I still went with the Radiomaster, and I am not looking back.
My 2 cents