Problem connecting wireless printer - Epson WF-3540

Very frustrated tryng to connect to a new Epson WF-3540, and getting wireless to print from MacBook Pro on OS10.8, as well as my iPad2, iPhone5.

Have followed directions to delete printer and reinstall, reset router, printer & Mac countless times and taked to 4 different support techs at Epson. Some reviewers have said they connected quickly with no problems, others experienced big problems like me. I can print from USB and Remote Print (although that takes a very long time). Epson keeps saying to call the router vendor. Our router is old and the vendor wants almost as much as buying a new one to provide support. But our network works fine with all other devices - the MacBook, iPad, iPhones, Kindle Fire, Samsung TV and Apple TV, Dell laptop, etc. throughout the house,so it really doesn't seem like the router or distance of the router to the printer. I did remove my cordless phone that was nearby. After that, as well as after the pings, previous resets, and re-installs, I can get the printer to print wirelessly from the Mac, iPhone, iPad one time and then when I try to print another document, it again says the printer is not connected, printer can't be found. I have read and followed all the steps on the Apple support site on printing, connecting a wifi printer, recommended settings for WiFi routers - all with no success. Does anyone have a solution? Are there any wireless all in one printers that work well with Macs (and iPad/iPhone via airprint) and also perform all the other functions well and are reliable?