Rad question for cooling a GTX285

Right now I'm running a eVGA GTX 285 SC (675Mhz), my goal is to watercool to reduce noise first and then maybe overclock it some more. I'm using a Lian Li PC-60FWB and I plan to later add a 320 radiator to the top panel to cool everything else. As of now though I was thinking of just cooling the GTX285.

WC Components:
GPU Block: EK GTX285 (EK-FC285 GTX - Nickel)
Rad: Feser X-Changer 120mm Extreme or Swiftech 120 + 120 stacker (when it's available)
Pump/Res: XSPC Laing DDC Res with MCP-350
Fan: 1 or 2 Scythe or Noctua fans (in push pull)
Housing: Lian Li EX-34B to replace 3 5.25" bays

According to the Watt Calculator on the FAQ, I would need to cool about 150W. I want to keep the noise at or below 25dBA. Will the two rad choices be enough to keep this cool and quiet considering the fans will be running around 1000-1200rpm and (I estimate) displacing about 50CFM? I know it depends on the pump, tubing, and fan... but is the Feser X-changer up to the task? Does anyone know the average amount of heat it can keep in check (considering normal and quiet fans)?

I would stick with the Feser rad and use the Noctua fans, also it's just preference but I would just use a XSPC Laing DDC top with the MCP 355 and go with the EK 5.25 x2 bay res.

I would second the shift to a 355, its just a much better pump. But I agree, the res top is the best pump top out there, imo

I have somewhat a similar setup except with the Feser Xchanger 240 rad on its own loop using the same EVGA GTX285 SC card. Idle is 40c, and 48 during heavy gaming. I have two Yates running at 800RPM. Its a very quiet setup in a low speed fan environment.
Running a single 120, you'll end up with probably the same idle temps, but your load temp will be higher with low speed fan(s). Any chance of going with the Xchanger 240?

@ohms/pwolfe: Based on some reviews and specs, I want to stick with the 350 because it's rated quieter (21dBA vs 30dBA -- the goal is quiet first then maybe overclock, but as of now I have no need to OC)

@MrE: I want to use the single 120 rad for now because I want to mount the rad + 2 fans in 3 x 5.25" bays using a modded Lian Li ex-34nb HDD enclosure. The 240 would require cutting somewhere (don't want it hanging off the back of the case). If I'm going to cut, I plan on getting the 360 (down the line when I add CPU, NB into the loop) for a top mount. Any estimate what the load will be with an ambient of say 25-30C? I'm worried I may burn out the pump on load which is rated to 60C.

Does anyone know how quiet/well the new swiftech stackable rads perform? I read somewhere that swiftech likes medium speed fans (i'm trying to keep this as quiet as possible), but I'd rather use 2 low speed fans in a push/pull config with Yate Loons or Scythe. I would probably use 2 x 120mm, is this going to be comparable to a 240 rad? Do the new stackers work cumulatively, ie 120+120=240, 240+240=480? I feel like it's going to be more like one and a half rads instead of a full 2, I guess due to the heat/air coming from the initial rad. I know the single stacker isn't out yet, but it may be an option.

:edit

Just an update. I assembled the loop over the weekend and leak tested and now it's up and running.

Before:
idle 45C/38C/42C GPU/CPU/SYS
load 81C/48C/50C

After
idle 38C/40C/45C GPU/CPU/SYS
load 51C/50C/52C

Temps are ok. There's a general rise in CPU/SYS temp, mostly because I replaced the main 140mm intake with the rad, putting back an addition 120mm fan for case intake above the rad (running parallel). Next step may be adding an RX 120.2 Rad and a Heatkiller CPU block.

I don't know how the heat load of a OC'd ATi 4870 compares to your card, but I'm cooling my 4870 with a standard MCP350, single MCR120 and micro Res, all running 3/8" tubing and a 2000 rpm Yate Loon at 7v. This little setup keeps my card at 32c idle and 41c full load (100% load for 30 min.).