depends also on your goal....if going for mass but concerned about adding body fat, maybe start with protein and add carbs as needed till you are satisfied with your gains.
you can also just add your own carbs to your protein, such as oats for example.
that way, you can customize the amounts of carbs that you want at any given time, and not be forced to consume the preset amount of carbs that are in mass/weight gainers. or you could also do both protein and mass gainer, and use the the protein at certain times and use the mass gainer at different times(such as peri-workout).
due to my work and travel schedule, I usually eat only 1 food meal a day and that's my last meal of the day that I cook before going to sleep. It is usually 1.25 lbs of beef(pre-cooked), plus 1 1/2 cups oats with 40 grams protein mixed in and lastly if I want to add something sweet in I'll eat up to 10 slices of toast with homemade strawberry jam(yummy). If I don't have beef, I'll eat around a dozen whole eggs instead.
during the day I will have protein shake every 2-3 hours to keep me satisfied.
Weight gainers are fine and I use to use them when I was young buts it’s not hard to get extra calories from food. If you can’t see your abs though defiantly don’t use a weight gainer because your body fat is too high already. Unless you are a powelifter or looking for absolute strength. How many calories are you aiming for?