I just find it amusing how everyone is resaying the same obvious things over and over. Its by human nature that we are able to get used to the gear we have and make do with it and eventually be used to it and play any game fine, given the peripherals were not absolute **** (stick keys, malfunction, etc).
Despite all that, you can't deny the small maybe negligible conveniences better peripherals offer. Better glide, better sensitivity (in relative to user's desires), better polling rate (anything over 500hz in negligible, although it will be extremely hard to tell the difference from 125hz as well) no pos/neg accel, no issue with/better lift off distance, sens swaps, extra buttons, ergo shape, etc can all help add up to your performance. Of course these are never NEEDED strictly to become a better/good gamer, but if it offers even the smallest edge then more to them.
Me personally, while I can stand using cheap peripherals for gaming and other everyday use, I prefer to use things that gives me the best comfort and feel and since I'm a computer geek I'm willing to drop the money on it. Currently using a filco brown nkro with steelseries xai (on 9hd). And yes I prefer hard mats over cloth mats for the glide, altho they eat away the mouse feet so much faster.... Also have a g5, g500 and an ikari lying around in the house as well as a mx518. Used to game a lot but with school I haven't found the time to play them like I used to... good old high school. If anyone is curious as to why I'm not using the g5 and g500, they're too heavy. I'm used to lighweight mice for lifting and what not, and it feels awkward to use on RTS games.
tl;dr: expensive peripherals do not help in the same sense raw skill does. use whatever you feel is the most comfortable as comfort is the key.
Oh and back to question at hand: I was also in the same boat as you, but since I don't game as much as I used to and tend to code a lot for CS classes, I went for the browns since they were the best compromise. I don't regret it at all, since its a blast to type on (maybe not fun, but its easy and comfortable) and feel great to use in games (RTS at least). The low force requirement hasn't been an issue for me at all, just have to get used to the lightness and you'll be fine. Although I honestly think people here are exaggerating the stiffness and discomfort of cherry blacks, but I'm starting to understand why because once you get used to the lightness of browns/blues, feels like anything stiffer like rubber domes are a pain to type on (Read: hard to type due to not being light keystrokes). Since you were last using a Model M, I think cherry blacks should be fine for typing and gaming.
So if gaming (FPS) is your main concern, I think blacks are the way to go. but I guess its too late since you're set on buying browns i think, lol.