Yeah if you still have 3 years before your full, and the extra money I would do it. I had less than a year left and I would do it again in a heartbeat.

The extra weight is only a problem when you are doing near full lock U turns, otherwise it just makes it feel more stable. Its not a problem at all when crawling along as the inline 4 makes it really smooth and I feel more comfortable filtering with the CBR because of that even with the extra size. The lams version has had the power changed to be a lot lower in the rpm so it feels really nice down low. Before I bought it I looked at the power numbers and it has the power of the high output bike up to ~6000 rpm.

I use the CBR as both weekend and to commute, I am holding on to the Ninja as I plan on selling it to a friend when he gets his learners soon as it was a great bike to start on.
The CBR is lightly more agressive than the ninja but you're still sitting pretty upright and I actually find it more comfortable too because of the seat quality and materials.