Depends on the 172 variant. I have a 210hp constant speed prop version that cruises at 128kts and will climb to over 18k. At 10k it does 32lph for a 145kt TAS. I rarely ever fly it VFR.
The 182 for the same performance is doing around 52lph.
Really depends non your profile, load requirements etc. A lot of the smaller 172 variants are pretty much a 2+2 if you want to go any distance. The bigger ones like mine are a 4 seat and 5hrs fuel. The 182 is similar.
You will get a 182 easier than an a big 172 though.
Maintenance is very similar.