Per my dentist wife. First, $400 is a steal. The downside is that over time, the teeth behind the gap will tilt forward, and could affect your bite. (Your teeth might not come together smoothly/comfortably when you bite down.) Her mother has a tooth tilted over 30 degrees.
This! My brother lost a tooth (not a molar) and at the time couldn’t afford to replace it. 10 years later he started having bite problems as per above post, his teeth shifted.
When he finally HAD to get it fixed he ended up with invisible braces first, then a bridge. It cost far more then $400 and far more then if he’d fixed it in the first place. Just do it!