I find that hard to say. He didn't have a 90 minute game with Groningen for months. He was seen as a talent at one point in the past, but so far has failed to live up to that promise at his different clubs. He got suspended at Groningen last season for being overweight. He has been struggling with his fitness throughout his career, but last season was a low in that respect. Perhaps a new challenge will provide the motivation to get his fitness back on track.
Then again, he was - at times - a useful player at his first season at Groningen, although he never was a 'big' goal scorer. He got 7 goals from a total of 42 Groningen appearances. He mostly was of use as the target man in the passing game (hard to translate to English), which I think is a rather typical Dutch style of play and I wonder what he has to bring to table in that respect in Scotland.
The Scottish game in general is more physical challenging than the Dutch (not sure if that also goes for the Championship though), and although it seems he has a lot of physique, I doubt it will be the right kind.
Its interesting to see what's going to happen with him at Hearts.