This bug zapper proved to be a capable insect killer, but with notable limitations. I also own a Stinger BK 300, purchased at a local big box store, and have had an opportunity to do a side-by-side comparison. These are my findings:

You'd think Flowtron could at least add an on-off switch, or, even better, a dusk-to-dawn sensor. But no such luck. This is a major annoyance. My Stinger shuts itself off at dawn. The Flowtron is on until you unplug it.

The BK-15D produces a brighter light than the BK 300, and hence, attracts more bugs. That's the most positive thing I can say about it.

Both zappers accept Octenol lures for mosquitoes, but those made specifically for the Flowtron are more expensive.

The Flowtron, like the Stinger, claims to have a self-cleaning grid, but that has not been my experience. Insect bodies seem to cling more to the grid in the Flowtron. I even posted a photo. The action of wind and/or rain will eventually clear them, but the Stinger just blasts the buggers into oblivion. All zappers require occasional cleaning, but the Flowtron seems more prone to this.

I have to give the edge to the Stinger, even though reviewers here have given it low marks. Mine is in its second year and still going strong. The Flowtron is a solid value, but has some considerable shortcomings. It may seem an unfair review, since the BK-15D is rated for 1/2 acre, and the Stinger is rated for 1 and 1/2 acres, but the Flowtron fell short on some of its claims, particularly the part about a "self-cleaning grid".

UPDATE: It's been 2 years since purchasing my Flowtron, and it's still killing the bugs. Although 'bare bones' in its lack of features, the BK-15D seems solidly constructed. As for the lack of an on/off switch, I was able to fix that with a dusk-to-dawn timer cord, basically an extension cord with a photocell switch (on at dusk, off at dawn).
This bug zapper proved to be a capable insect killer, but with notable limitations. I also own a Stinger BK 300, purchased at a local big box store, and have had an opportunity to do a side-by-side comparison. These are my findings:

You'd think Flowtron could at least add an on-off switch, or, even better, a dusk-to-dawn sensor. But no such luck. This is a major annoyance. My Stinger shuts itself off at dawn. The Flowtron is on until you unplug it. The BK-15D produces a brighter light than the BK 300, and hence, attracts more bugs. That's the most positive thing I can say about it. Both zappers accept Octenol lures for mosquitoes, but those made specifically for the Flowtron are more expensive. The Flowtron, like the Stinger, claims to have a self-cleaning grid, but that has not been my experience. Insect bodies seem to cling more to the grid in the Flowtron. I even posted a photo. The action of wind and/or rain will eventually clear them, but the Stinger just blasts the buggers into oblivion. All zappers require occasional cleaning, but the Flowtron seems more prone to this. I have to give the edge to the Stinger, even though reviewers here have given it low marks. Mine is in its second year and still going strong. The Flowtron is a solid value, but has some considerable shortcomings. It may seem an unfair review, since the BK-15D is rated for 1/2 acre, and the Stinger is rated for 1 and 1/2 acres, but the Flowtron fell short on some of its claims, particularly the part about a "self-cleaning grid". UPDATE: It's been 2 years since purchasing my Flowtron, and it's still killing the bugs. Although 'bare bones' in its lack of features, the BK-15D seems solidly constructed. As for the lack of an on/off switch, I was able to fix that with a dusk-to-dawn timer cord, basically an extension cord with a photocell switch (on at dusk, off at dawn).