Writeshields are expensive though =/ Maybe it's worth getting the Writeshield anti-glare...if it doesn't get scratched. Does it? (my boxwave is literally covered with scratches...yes, i like its consistency matte feel, but every once in a while a little piece of something gets stuck on my stylus and it scratches as i write, leaving the mark on the protector)
Technically, I didn't buy an invisibleSHIELD but I bought a DIY sheet from a site that sells the exact same 3M stuff that invisibleSHIELD uses...
http://www.bestskinsever.com
I dunno, i'm hoping i'll be able to cut it perfectly and it'll do well for my X51v. Hopefully it won't be too sticky; if it is i'll go buy a writeshield i guess.