I like the RTC approach simply because it's less hassle. If you don't want to drop $15, you can get the DS1307 in a DIP package for $4 from Digikey (of course, then you still need the battery, the crystal, etc). You don't even have to convert the values from the RTC -- they are BCD just like the 74141 expects, but you do have to mask off the AM/PM bits, clock enable, etc.
My project is going to use four large LED-based 7 segment displays, but the clock functionality is kind of a side thing.