Help buying new Canon dslr

Hi I'm Looking to upgrade my Canon 30d I've been looking at the canon 5d classic (12.8mp) or 1d mark II. I shoot mostly indoor low light event photography with the occasional portraiture. I'm looking for something that handles noise better my 30d is seeing its day. what im looking for is something that has good IQ and low noise. out of the two. Portrait and events is my go to gig I dont shoot fast action sports. my budget is $600 USD

Any help be welcomed

Current Gear: canon 30d, xti, sigma 28-70 f2.8, 50 f1.8, efs 18-55, 70-300 non is