I'd like to get a BT keyboard for my N800. I've read a number of the threads in this forum and it seems that iGo stowaway is a good choice. For me, lighter is better so that would suggest the 4-row ultra-slim. Can someone confirm how one types numbers on this keyboard? I'm assuming that it's in combination with one of the two Fn keys. Any opinions - how inconvenient is it to use a Fn key for numeric input? Is it worth the extra weight for the full 5-row stowaway? Are there any other pluses or minuses to consider?

Thanks for any thoughts.