The Akademik Ioffe is the ship I chose to take my expedition to Antarctica on. While it can seem a bit spartan, it gets the job done. Aside from the two days crossing the Drake Passage to get to and from Antarctica, you probably won't miss the other creature comforts too much.
One tip for choosing a ship to cruise to Antarctica on: make sure the passenger capacity is under 100. Tour operators that belong to IAATO, which is probably all the operators that you would find for a proper trip, abide by rules that allow a maximum of 100 passengers to be off the ship at a time. If you choose some luxury liner that holds 200 or 300 people, your time on land in Antarctica will be limited far more than on a smaller vessel.
On the Ioffe, we made two excursions a day. Depending on the conditions and locations, these were either a zodiac only excursion (rare), or a landing with a potential zodiac cruise as well. This works out pretty well as you end up having breakfast, going out for a few hours, and then making another excursion after lunch.
Former Russian 'research' vessel turned Antarctic cruise expedition ship.