I agree 7.1.3 is the latest (I went to V8 from 7.1.2 so can't testify to 7.1.3)
One problem is much of the slowness you will see with the V7 series as well as the V8's
V8 may be SLIGHTLY slower but not by a lot.
I would recommend you compare speed with the 7 series with the 8's but not radically different in speed.