Someone recently asked me this question. To tell you the truth, maybe.
If you are going to collect full panes of stamps, don’t do it for investment purposes. Most modern issues (year 1935 and later) don’t go up in value. I don’t recommend buying these kinds of stamps with the thought of making money over time. If history is a predictor (and it usually is), mint panes of stamps are not a good deal.
If you like full panes of stamps and it’s what you want to collect, why not? The point isn’t how much money you spend on your collection and how much it will be worth when it’s time to sell. The real “profit” you get is your years of enjoyment out of your collection. If full panes of stamps are your cup of tea, by all means, collect them and enjoy your hobby. Collect what you want to collect, not what others tell you that you should collect.