You will get enough volume, but what you might miss compared to the lower impedance versions, is a big dynamic range. This means, that if you turn up your phone on the loudest volume, it might not be able to put out enough power for the loudest sounds (could be a very energetic passage), and thereby it will clip, and sound unnatural and unbalanced.
This is what will happen, and i don't think it will sound extremely bad or anything, but idk... IF you go buy the 250 ohm edition you should get an amp some time. If you won't get an amp, go for the low impedances.
But the phone really does improve with an amp, at least my dt-880 does. You get a more full and more musical sound, the highs improve a bit, the lows a bit more, and the phone seems more transparent and the soundstage improves.
This alone might not justify spending 150$ on an amp, but if you eventually will get another phone, or going deeper into head-fi, it will definetely be worth it. Also cheaper amps could be a solution