What model? If you have the rlc, it costs a lot less to get the push upgrade than if you have an r or rl. That will have to factor in to your calculation. Anyway, even if you don't want their upgrade, you can send your fork to push just to get the normal talas service. I don't think that that will cost much more (if at all) than sending it to Fox for the talas service. You'll definitely get the fork back quicker if you send it to push.
I went from a talas 125 rl to the push rlc. It's good, but can I say that it's better than before? Beats me. I'd been riding the fork for several months when it needed the talas cartridge serviced badly, and I was off the bike for 3-4 months anyway when it was serviced, so it's hard to say how different the fork feels. It's definitely better than when I sent it in, but that could just be because the talas cartridge is working better now.
Everyone's going to tell you to get the push upgrade. You might as well just cave in and do it. I'm happy enough, although I gotta say, I don't really like the push stickers (edit: Ha! Didn't see JSD's response).