Should I consider getting an emissive spectrophotometer like the i1 display and reflective for measuring substrates etc? If I were to get a wide gamut monitor later, is that going to be an issue? My budget would be up to $300 or so $400 would be tops.
I would appreciate some discussion of viable options.
At your 300-400 budget level, Andrew is right. The Colormunki is about your only option. If you stretch the budget to $500-600 then the Datacolor Spyder3Studio SR kit can also be considered. This kit includes a transmissive colorimeter for calibrating Displays and a reflective-reading colorimeter for making print profiles. Datacolor describes the reflection unit as a "spectrocolorimeter" probably because it uses more filters than a conventional 3-filter colorimeter, but whatever you call it, it's not a full-fledged spectral reading instrument. Nevertheless, any unit that can measure and report CIELAB color values with reasonable accuracy is a huge step up from no ability to measure and track color quality at all. Additionally, like the Colormunki, the Datacolor kit integrates the hardware quite closely with the available software, so there is no where near the upgrade pathway to more sophisticated software packages that support instruments like the i!Pro. For the Professional printmaker the constrained (some say "crippled") software of these low end packages puts the i! Pro in a different league than either the Colormunki or Datacolor kits, but now your pricepoint jumps to about $800 street price for the bare-bones i1Pro basic unit, and well over $1000 once you start adding the more versatile software that the i1Pro supports.
I was curious about the capabilities of this Datacolor system and actually purchased one about a month ago. I haven't had a chance to do an in-depth evaluation, but in my "kick-the tires" testing the Datacolor Spectrocolorimeter SR is very fast and reasonably accurate. Is it analytical grade instrumentation? No, of course not, but it does appear to satisfy the intended purpose very well. It is going to allow you to calibrate monitors and profile inks and papers for which no generic or canned profiles exist. If you live only in an Epson OEM universe of printer/paper/ink combinations, one could make a good case you won't need print profiling capability, but once you expand your horizons much beyond a tightly integrated OEM printing solution, instruments like the Datacolor or Colormunki become very justifiable instruments to own.
Both the Colormunki and the Datacolor Spectorcolorimeter are UV-cut instruments, so they won't tell you much about OBAs in your chosen papers, but that is an academic issue if you stick with OBA-free or very low OBA content papers.