each to his own as they say, i prefer WRT in that
1.) has a better div yield than WDC.
2.) WRT is trading way below its NTA of $3.45
3.) WRT is trading on a PE of only 11, WDC is 16
but like you say WDC is more diversified than WRT.
If i had a choice to buy WDC at $8.50 or WRT at $2.85
Id probably go 75% WRT and 25% WDC.