The 480 has the same performance as the 750 ti, which does fine in 1080p games. Granted the 750 ti does have 500 GB more of VRAM, but I'm not sure it (nor the 480) have the processing power to fully utilize it anyway. The 750 ti is only $150 new, though it can't do SLI. That said, you might be able to get a pair of 480s for about the cost of a single 750 ti. In that case, I'd say it's a pretty good cost-to-performance scenario. Games that can't use SLI generally aren't the most demanding titles, so a single 480 would likely be able to run them. For games that can use SLI, you'll get pretty solid performance, as others have pointed out, on par with a 770. For the money, it's hard to beat (see e.g. this eBay listing for a pair of EVGA 480s currently at $130: http://www.ebay.com/itm/2-EVGA-NVIDIA-GeForce-GTX-480-015-P3-1485-AR-1-5-GB-GDDR5-SDRAM-PCI-Express-/261478707476).
When it comes to combingation of performance, stability, compatibility, and power efficiency, however, you'll likely need to spend more money on a modern single GPU to get the best balance. This decision will mostly depend on your budget. Good luck!