I personally have had no problems with the Irritrol controllers, I dont use them often but when I do I find them very easy to program and operate and have not exeprienced any failures.
I would question the logic of switching brands based solely one problem in four years of "otherwise...excellent" operation.
I would recommend you contact your installer, local Irritrol distributor and/or Irritrol as the warranties on these controllers can be quite long, but are often applicable only to trade professionals, not homeowners.

In fact I just google'd "irritrol warranty" and found the following: http://www.irritrolsystems.com/service.html

As for your question regarding wireless connectivity of irrigation controllers to your PC, I would recommend you Google it and see what you find. My first query result provided an answer to that question.

Good luck!