Well, I've been using the K90 since it first came out. And it's a great racket, I love it. But just out of curiousity, I wanted to try out the Yonex's most precise racket. The first thing I noticed was the weird head shape. It was very square. When I compared it to my K90, (put it on top of eachother), the headsize seems a bit smaller than 90. Part of the headsize was cut off in the corners. But it was a bit longer up and down. These characteristics were very subtle, and I could barely catch them. Anyways, They had that same type of paint, not that glossy kind but that sort of ... graphity kind? They are both very good looking rackets. Also, because of the weird headsize, the string pattern seemed a little denser than it really is. Also, since the beam is a little thicker, I thought i would frame a lot, but I didn't at all. Now, my playing level is 5.0. I am a junior player, and I was rated by my coach. I hit the sweetspot 9/10, and almost never "shank" the ball. Now...Onto the way it played. So, as a warm-up, of course, I started at the service line. Volley to volley. The racket was VERY, VERY, VERY, crisp. This racket punched the ball back deep. Very deep, and yet, it was touchy enough to give the best drop volley, and touch shots. I loved coming up to the net with this racket. Whenever I did, I could punch the ball into the corners past my opponent very efficiently. Also, every once in a while, I would just tap it over and it would be the perfect drop volley. Now, when I moved back to the baseline, I hit the ball back deep, without effort. This racket IMO, was VERY control oriented. What I put into it was what I got. If you have a slow swing, you won't like this racket too much. Long, fast, agressive swings give good depth, power, control, and spin if you want it. This racket, is a SPIN MACHINE. Even though the string pattern looks pretty dense, it's still made tons of spin. The racket gripped the ball very well, and once you were done with your swing, the ball few off the racket with more spin than Nadal. (Maybe not that much.) This racket was very stable. When I blocked the ball back, the racket felt like it didn't shake at all. All I have to say for stability. Now, for service returns, this racket didn't shine too bright. It was pretty hard to block the ball back, because it was hard to match up the ball with the sweetspot. As you all know, for a mid, if you miss the sweepspot, then you probably already lost the point. Since we're talking about service returns, lets go on to serves. This racket also didn't shine to bright on serves. Even though I could place it ANYWHERE I wanted in the service box, I couldn't get enough juice on it. Like I said before, what you put into it, is what you get out of it. I couldn't swing hard enough to get that usual speed on my serves. Unlike the K90, which is a rocket launcher on serves. But you know, it was quite easy to "put into it" because it was quite manuverable. I don't know why my serves were lacking power so badly though ...:-| Anyways, the last topic, CONTROL. This racket had PINTPOINT control. I'm not kidding when I say this. People just say that to describe how good the control is, but this racket, could read minds. You just swing the ball, tell it to go to the deuce side corner, it'll just catch the lines, and go right past your opponents. Also, if you want to pull your opponenets out wide, just swing at the side lines, it'll be just inside. This racket's control is unmatched. (Except maybe by my K90). So, as you could tell, I really liked this racket. The power was good because of its manuverability, I could put the ball on a stringsaver because of its control. This racket was also very comfortable because of its lack of shaking - from it's stability. There's just no way you could go wrong with this racket. Now, when I compare it to my K90, I would say the K90 is better. I'm not just saying that because it's the racket I use currently. I'm saying it because the K90 is in my opinion, a lot more manuverable (because yo ucould just whip it through), stable as superman, you could put so much spin it would cut through wood, and control is just as good as the RDS 1. The K90 is pretty much the RDS but slightly better in every category. The RDS mid is a good move if you want to move on to mids, but not yet ready for the K90. Why? Because the K90 is a big demanding. It's sweetspot is smaller than the ball. Summary - Yonex RDS is a good racket for mid users. K90 IMO is sort of better. Yonex is good for someone just moving into mids. K90 is for someone who's got the hang of mids. Yonex RDS is good in every category. So is the K90.