i've been sewing for 45+ years- and love my cheap, cheap irons...i've over the years had a couple (high-end) irons which i hated and would wind up going back to the $20 or less irons.
I never ever put water into an iron- i hate sputtering, spitting, leaking irons! i keep a spray bottle of water on the end of my ironing board when i need to press a seam nice & flat- or need a spritz of steam on any block i simply spritz with my spray bottle then press- works great.
remember there is going to be (layers) of fabric where seams are- so they are not actually totally flat- as long as your seam is (crisp) straight & smooth you are probably doing just fine.
I have found i normally have to replace my cheap-o iron about every 3-5 years (although i've had a couple that lasted longer) but i don't mind- figuring i had to replace that last $159 iron in less than 3 months!
i know there are people who swear by the expensive ones & love them- i am happy they have something that works for them (i do have to wonder though how often they buy a new one???)
in my mind (since i used my grandmother's iron for almost 20 years after she passed away & i don't know how long she used it before me) i think an iron should last a good long time- not a matter of months....just my opinion...