Just be careful when tracking that you're not using any CPU intensive plugins like Perfect Space (or any convolution reverb) or any look ahead plugins like the ProChannel Concrete Limiter.
Other culprits in Sonar are the LP-64 EQ and LP-64 Multiand Compressor.
When tracking I disable these plugs, or don't use them until the mixing stage.
If, for example, a singer wants to sing through a reverb, I always used to use Pantheon, or now Breverb, as they don't seem to induce any noticeable latency.
BTW, I do tend to let them sing through the CA-2A (PC2A as was), because it sounds great, inspires them to sing better, and introduces little or no noticeable latency.