I think the split will not serve you well as a natty bodybuilder who also wants to build mass. That's not to say that you have to do a whole body workout, although I'd say that full body 3x a week will be better compared to the strict bodypart split that most juiced bodybuilders use. Somewhere between the two will probably be best. In the 80's it was popular among bodybuilders to hit everything twice a week, which would be a good base upon which to make your own training program.
Remember, the bigger the muscles you use, the more testosterone will be released.
The workout program you use actually isn't as important as diet when it comes to bulking versus cutting. The same well-designed program will work for cutting or bulking, so choose one, buy into it, and stick with it for a while.
The truth is that if you're a bodybuilder, diet is far more important than the way you program your workouts. If you want to build mass, then you're going to need to eat over maintenance. You need to find out how many calories you need to maintain your current weight, and add 200-500 calories a day in a controlled, planned manner. 500 calories a day added to your maintenance diet will result in about 1lb gained per week, which will almost certainly be mostly fat, so start easy with around 200 extra calories a day to see how your body reacts to increased intake. If you're strength is going up and you're muscles are filling out, try increasing the extra calories.
I'm a believer in cycling carbs, which is a complex concept that I've simplified to these rules;
1. Eat as few carbs as possible most of the time.
2. Eat lots of proteins and good fats most of the time.
3. From 1 hr before training to 2 hr after training, eat lots of proteins and carbs with very little fat.
These rules apply all the time, bulking or cutting. The only difference is the number of calories, which is over maintenance for bulking and under maintenance for cutting.
Whether you follow this plan or not is up to you, my point is that diet is WAY more important for a bodybuilder than training splits and programs.