HiTech has completely free Light version for PIC16F84 - you can use it without any limitations. The price is not that expensive if you're professional - in fact you pay it out by doing a single project.
If your projects are not commercial then the standard License is enough which is quite affordable.
And if you are not into very complex projects, you will not reach the limitation listed.
And most important is that it does a very good job for its price.
I used to program in ASM in the past but as my projects got more complicated I tought its time to try a C compiler.
Used Hitech compiler (free) for a while but did not like it very much so started looking for a better compiler.
Then came across Sourceboost and after reading some reviews I decided to give it a try. I bought the standard license (which is quite affordable) and haven't looked at ASM or Hitech again.
Been doing small to medium projects without problems.
Thats all I can say.
If you compare how compact is the code generated from HiTech and other compilers you'll find out that HiTech code has smallest size and could be executed faster. Of course other compilers could offer some useful libraries or wizards but as C compiler HiTech is considered as the best compiler for PIC (as IAR for Atmel processors). Notice that HiTech company was acquired from Microchip, so when you talk about HiTech you should think about Microchip.
I like mikroC more than the other compilers, because of their library functions, tools and because it's quite cheap. Support is good as well and all my projects with PIC and AVR have been either with mikroBASIC or mikroC.