Originally Posted by kv501

4700 Tiagra is 5600 105. Shimano trickles everything down when new groups come out. It's the same way with new 105 (5700); it is the same as previous Ultegra for the most part. It has the smaller hoods, cables under the tape, etc... 10 speed has moved its way down year by year from Dura Ace to Tiagra, 11 speed is down to Ultegra now along with Di2, and it just keeps going this way.

Now that you're confused I'll give you my opinion . If your budget is limited and you want 10 speed, go with Tiagra. Like I said before, it's the same as previous 105 and as long as you don't care about cable routing it will work just fine for you. I rode 5600 105 for a long time and never had any trouble at all. I do think it's more durable than the groups below it.