I have the Yamaha MSP5 which has TRS and XLR input. I understand that XLR is better that TRS so should I get an audio interface that supports XLR output? If yes, which Audio Interface is recommended?
No lower-end audio interface has XLR out for size/cost reasons, so you might be looking at an unnecessarily hefty investment (forgive me if I'm wrong, but I'm assuming you're not doing pro-level work based on this question).
I suggest just using a 35mm to 1/4" converter (a couple bucks at an audio/IT store) to get it working with your iMac right away.
twoteaspoon, you are looking at capacitance when comparing the 2 plugs. The lower the better for the case of line level cables to speakers.
You can use a TRS to XLR cable to connect from a consumer level soundcard if you believe the XLR plug has lower capacitance. Operationally, they both are balanced cables so should function the same.