30-32 for every day use, (depending on how many passengers or loads you carry) is fine. I run all mine a 32 and has been fine for years. Also did on my ep3 too.
With regard to what inflators.... I use any garage air or have had nitrogen in too, but I always over inflate, and then use a digital tyre pressure reader to get them accurately the same by letting air out if need be. Some of my local garages are inaccurate. I've filled up to 32psi using a sainsburys one, and it was actually 28 according to my reader. Haha yet some have been almost spot on.