Yaesu FT-817ND for QRP Phone?

I don't claim to be an expert on ham radio.  I do try to keep up with stuff and read a lot.  Some day, I'd like to get a radio that is more portable than my FT-450.  I've considered the FT-857D and the FT-817ND.  Obviously, the 857 has more punch, filtering and other options.  Yes, it is almost $800 at the time of this writing, and weighs a whole lot more than the 817, and requires a battery in all portable operations.  In contrast the 817 is about $200 less, has minimal filtering and only 5 watts.  It does have the internal battery and a AA battery pack--handy features if needed.  I guess my question is basically, all things considered...would 5 watts or less be able to do much on phone SSB?  I can see an antenna being a homebrew dipole/vee, EndFedz or something like a Buddipole/Buddistick.  Unlike a lot of people who buy the 817 for CW, I don't know any morse right now.  So, I'd be limited to voice, or perhaps digital mode, such as PSK-31.  So, I'd appreciate comments by anybody who drops by my blog.  Thanks, Steve.