As per latest statistics from National Crimes records bureau for year 2009. Section 498a has second lowest conviction rate in india compared to other criminal section. The only other section under which there was lower conviction was arson (IPC 435, 436 and 438) and that too beat 498a by mere 0.3%
Here is hard statistics for year 2009
1. Conviction rate under 498a ( across India) 19.8%
2. Conviction rate under arson ( IPC 435, 436, 438) 19.5 %
3. Highest criminal conviction rate( other Criminal IPC) 53.6 %
Official statistics link
https://ncrb.nic.in/CII-2009-NEW/cii-2009/Table%204.12.pdf