I have 8 inch drivers on my 1998 SRX and am using 23:37 gears. If I could find a larger top or smaller bottom gear I would install those. Your SRX should easily pull these gears with the 8 inch drivers.
The other modifications I have are a team secondary and an M-10 rear suspension with Ohlins, 1.25" Ripsaw track, and high compression billet heads with the appropriate carb jetting.
I put less fuel in this sled during fill ups than any other sled that we ride with (Arctic, Polaris, or Doo's) averaging over 17 MPG.