Planning a trip EWR-TLV and trying to figure out an efficient way to do it. I want to pay cash rather than miles because I want the PQMs (might make gold this year if I do)

Okay, since my schedule is a little flexible I've got 2 choices:

1) I can find a deep discounted fare for $12XX RT. If I do that, I'm sitting in coach. I'm not spending a $600 copay plus 35k miles each way to upgrade.

2) I also found a class B fare for $1,726. Yes, this earns 150% PQMs which is great, but I'm not interested in paying $500 extra just for the extra PQMs.

On the other hand, B gets upgrades with miles without co-pays and I'd gladly buy B if I could be assured of being able to upgrade with 35k miles each way.

So, does anyone have experience on how likely it is to be able to upgrade with miles (in both directions)? If it's something like 80%, I'll chance it. It's it's under 50%, I don't think so. If I could only upgrade one way, it's kind of a push, but maybe the extra 50% PQMs make it worth it.

Thanks!