This is always going to be a difficult question to answer because for some people going up a size or two can have a detrimental, not beneficial, affect on their shooting.
On the other hand an awful lot of people have made the change successfully and wouldnt dream of going back the steady swing and smooth shooting characteristics of the bigger gun suits them down to the ground.
Choice of gun should always be dictated by personal physique so if youre of slight build a heavier gun like this might prove a little tiring to use.
If so, stick with what youve got.
What I will say is that one of the advantages of a long barrelled gun is that it lets you point out a target better than a shorter gun, especially on long range birds and particularly those that quarter away from, or across, the shooting position.
A well balanced, long barrelled, gun is definitely worth a try but dont expect it to perform miracles straight out of the box; it takes time to get accustomed to both the way it moves and the different sight pictures you get with it in relation to the target.