Canon EF 24-105 f/4 L question

[Photog82]

I'm considering purchasing this lens to replace my Canon EF 28-135 lens. I've found that this lens has been around for 7 years now. I'm wondering, if this lens is aging now and should I wait for a MKII? I'm also concerned that the MKII will be much more as recent lens releases from Canon have gone up in price.

I have a 40D that I'm attempting to sell and want to either purchase the 60D or 7D. I'm not planning moving to a FF body as they cost too much for me and I'd rather spending the money on glass.

Any insight, advise, etc would be appreciated. Thank you!

Edit (added my lenses):
Canon 10-22
Canon 70-300
Canon 50 1.8
Canon 28-135