As a former salesman this is my element!! =D
First off: is the SV the faired SV650"s" or the naked SV650? I have the naked one. Working on it wise, it is super easy. Shim under bucket valves are the only bad thing about them. And alot of people turn them into track bikes so while they are not the typical Inline 4 fully faired sportbike, they are still popular and track compatable.
I have never owned a Yamaha, never even rode one truthfully so no pros and cons from me...
I used to ride my brother's CBR600rr often. Great bike, but if you want to touch it with a tool your going to take off all the fairings which is a pain but part of the territory and since it IS a Honda you'll have a pretty solid machine.
The F4i is really just a more street friendly version of it's track bike brother the 600rr. And truth be told the 600rr is somewhat detuned in comparison to the other big Japanese brands; lower end power, less top end punch, etc. So...
If you are anything like me, you would go with the R6.
The reason you have for getting one is a good one, you want the real deal while you can still physically not loathe it...
If you get the SV, your going to think sometime somewhere in the back of your head that you got a V-twin when you really wanted an Inline 4.
If you get the Hondas, again in the back of your head you'll know you got a detuned version of the nastiest (I mean the in a good way) bikes in the world.
The R6 is the real hard and tough supersport of the bunch. It is a little bit harder to work on than the SV due to the fairings, but it is still not very hard and if you get in over your head just remember that it is a Jap bike and parts and mechanics are everywhere.
On a side note....Insurance costs. The SV is dirt cheap compared to the others, but even though the Hondas are more tame, you wont see a significant kickback in your premiums, it would be the same as the Yamaha.
Well...I've spoken my 2 cents =D Hope it helps!
but would still consider one. 
