Design change: The color of the laser it fires has been changed from red to blue.
Update 1.16.10
Rarity change: Rare → Super-Rare
Update 1.30.4
▲ Strength change: 4 → 5
▲ Health change: 6 → 7
Strategies
With
Laser Bean is a 6-sun 5/7 plant, which isn't very astounding. But thanks to its Strikethrough trait, you can use it as a finisher or late-game card, where it can alarm your opponent to react to a plant that always (barring Super-Blocks) chips a quarter of their maximum health per turn. It is a very reasonable 'big drop' in the mid-to-late game, because of its solid stats and the ability to pressure your opponent, and it is also a solid card in many 'mid-range' Solar decks which aim to drop one big card every turn.
Each hero has their own unique strategy to use with it. Wall-Knight can use Pecanolith to ensure that it does 7 damage instead of 5 (it will weaken as it takes damage, however), Solar Flare can increase its base strength, and Chompzilla can use boosting cards like Grow-Shroom on it or use Umbrella Leaf to give it Untrickable. Rose could take advantage of bean synergy, but bean synergy is not a good idea as most bean decks cannot last that long; instead, the best she can do is to shut down any zombies that threaten it with Freezing and Bouncing.
However, it is expensive, so it is recommended to quickly ramp up sun to drop this earlier where your opponent may not be able to handle it. Laser Bean is also vulnerable to removal and doesn't have any immediate effect on the field. It also lacks synergies, only having raw stats so it may not be more useful than others.
Against
Laser Bean can be harmful if you leave it alone for too long; it may have average stats, but you have to stay aware that it can still constantly do 5 damage to you every turn. But otherwise, it shouldn't be a huge worry to see on turn 6.
If it seems to be getting in the way, you can easily remove it. Although its health may be an issue to you since 7 health on turn 6 is still a lot, instant-kills can negate it.
Gallery
Plants vs. Zombies Wiki has a gallery for Laser Bean (PvZH).