I have a hobbico spectrum. I love the plane, it is very acrobatic and very fast. Almost too fast. it takes a long time to bleed off speed and stalls rather quickly. Since I'm landing on some pretty rough grass it can be a little hair raising. I have already had to change the landing gear location (the gear is notoriously weak on this model anyway), and i've gone to bigger wheels.
It does have separate servos for the ailerons. Currently this is going through a Y connection and into one channel on the receiver. But it would be very easy with my radio to make them flaperons.
Is this advisable? Would it really help? and what kind of flight characteristics can I expect?

I think flaperons would depend on the size of the ailerons to actually work, it would probably make a difference in flight characteristics

what prop are you using?

I have an os .46 FX spinning an APC 11X8

The 11-8 is a bit stiff for an FX (it's a 60-size prop). Try an APC 12-4 -- you will lose a chunk of speed at both ends, plus gain a ton of vertical. Top level speed will be ~ 60 mph & the landing speed will fall off a lot -- you probably wont need flaps.

yep... agreed... I use the 12.25 x 3.75 and love it... plenty of get up and go... but slows down nicely

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Flaperons can aid in lowering landing speeds, BUT.. when deflected a lot, the drag they add is also a lot, and the nose must kept down, because of the two problems which flaperons create. Tip stalls first. Dropping the trailing edge reduces the angle of attack at stall, the plane will stall sooner than it will without the flaperons.
At large deflcetions, with a roll command, the aileron that should go down can't.. it's already down. The other aileron goes up, which reduces the drap on that side a LOT. The down aileron drag then pulls the nose -opposite- to the commanded direction. which is VERY disorienting when first experienced.
I'd recommed going to a flatter pitch prop, as britbrat. I fly a Morris Top Cap with the OS 46 FX, and it's quite happy with a Zinger 12x4.

Picked up an APC 12x4 on my way home from work. All I have to say is WOW! I knew how fast that engine could run, the first prop i had on there was a 10X7 and it just screamed. But now I know how hard it can pull. I havn't had a chance to fly it yet so I don't know if it has slowed down the landings, but can't wait to get to the field and see how fast this thing can go straight up!

The larger prop puts the rpm closer to the torque peak of the motor, where it really shines.
The small prop is for flying very fast, but without the vertical from a standstill.