Is reading inscriptions hard?

I have been visiting many Roman sites, but my Latin is quite rusty. I participate mostly in the Greek forum. I was wondering how much easier it is to learn to read inscriptions than full texts. And, are there any good guides (online) explaining how to do it–common schemas, etc?

Thanks.

http://www.archive.org/details/introductiontos03egbegoog

http://www.dl.ket.org/latin2/grammar/inscriptions.htm

http://www.case.edu/artsci/clsc/asgle/abbrev/latin/