Get to L90 ASAP, and lets hope they then have a free rental. If you want the best scoring potential going for or otherwise it's L90 R11s all day from the tips at any rate, but the meter is too quick for a few. If I was OK with it sure you will be but only you can decide.
All that said there is no rush. Come the free rental (hopefully soon) try them all, but give yourself long approaches to get a feel for what is to come at Legend which is where you are now looking. What you have is fine until you hit the tips. Of course they could replace the R11s next down time. Whether that is good or bad is guess work, but knowing what I know now I would say wait until you are Legend before actually buying..
Your current irons are good, and hoe they do start performing for you again soon. Hopefully just a little down turn in form that even the best suffer from now and then:)