I took the plunge on the 85 1.8 and was skeptical, when i snagged it (along with the 50 1.4) I bought them at my local store and before buying my question to them was ---- what is the return policy here? LOL. I thought this for a couple reasons - I have a 24-70 2.8 and the 70-200 2.8 (non IS version, which, that one may not be a bad option if you have a steady hand!!!!). Also, there was a big part of me thayt said these are cheap, so they could never stack up with the L lenses and hold their own. Another factor - when i bought them it was actually a desperate attempt to make my 7d more usable (cause though i love it, it just does not keep up with the 5d3. So, yeah, why do i need these little primes when i cover both focal ranges already?
To my surprise, these little primes rock. Screw the 7d, I use them on the mk3 for a variety of purposes. I favor the 85 over the 50 for sure (it's a touch sharper i think, and I am just kind of in love with the field of view it offers). Build quality wise, yeah, they don't feel as sturdy as the L lenses. I wouldn't want to have them on camera in questionable weather. But, all that said on a general portrait shoot I use the 85 quite a bit. And yes, using the 85 does make me want the 135 as well!!!
As to the idea of waiting for the upgrade on the 135L, I honestly wouldn't worry about that. Everything I have heard about the 135L is that it's "magic". Plus, who knows when it will actually be upgradd, and ---if Canon follows its recent trend with primes, it may not be the upgrade you want (IE: it may not be 2.0, it may be 2.8 and with IS and tack on an extra $500-1000)