I note there are very few reviews of the Arctic cruises and can't see any of this ship for this itinerary here so hope this might be helpful to someone:
We spent 7 nights on the MS Expedition (G adventures ship) and one night in Longyearbyen - all booked through Explore.
The ship: We loved the Expedition, it was comfortable with loads of communal space (bar, library, lounge, big observation decks) and our twin cabin was larger than we expected. The mud room for storage of outdoor stuff definitely made 'suiting up' quicker and easier, and we were given muck boots and a parka - the parka we got to keep - saving plenty of luggage space on the way over at least. The food also exceeded expectations - yes there was plenty of stodge and multiple crumbles with custard (not complaining!) - but also lots of choice, fresh fruit and salads, and the dinner service was amazing. The crew in general were great - from the cabin cleaners to the waiters and barmen - very hardworking and friendly. There was a lot of effort made to entertain, from deck BBQ, to a resident musician, a quiz night and themed buffets. The atmosphere was warm and it was lovely to share experiences with others aboard - although you also had plenty of space to be alone if preferred (other than dinner - communal tables).