Sprint (S) is no longer the slug of the wireless industry, according to two new surveys of network quality. And their underlying data suggest that a combination of the network with that of would-be merger partner T-Mobile (TMUS) would yield even better performance than simply adding up coverage areas would suggest.

Whether going from four nationwide carriers to three will leave enough competitive pressure in the market against the two biggest carriers, AT&T (T) and (Yahoo Finance corporate parent) Verizon (VZ), is another thing entirely.

Surveys like these don’t try to answer that question, but regulators will have to before deciding whether to approve the merger Sprint and T-Mobile announced in April. If they allow the deal to go through, a large economics experiment will begin to unfold.

We could pay more for service that’s not much better than what Sprint’s already delivering, or we could find that a stronger, combined firm both keeps the pressure on AT&T and Verizon, and even use 5G wireless to challenge their wired residential broadband. You have to ask yourself: Do you feel lucky?

Sprint’s progress

The two reports released Wednesday from OpenSignal and Speedtest, based on crowdsourced testing on phones running their eponymous apps, concluded that even as wireless has gotten faster overall–with T-Mobile and Verizon now essentially tied for their top honors–Sprint has staged an impressive comeback.

The two surveys each ranked T-Mo and Verizon in first and second place–for instance, OpenSignal found T-Mobile’s downloads averaged 21.57 Mbps and Verizon’s averaged 20.56 Mbps at the latter–but didn’t find AT&T and Sprint behind by much. OpenSignal, for example, reported AT&T downloads at 15.08 Mbps and Sprint’s at 14.46 Mbps.

“Sprint has delivered the most improved download speeds over the past year,” Speedtest’s report noted. Its uploads, however, continue to lag in Speedtest’s data, thanks to that carrier setting its network to favor downloads; OpenSignal’s found the same pattern.

OpenSignal also tracks “availability,” the time a phone running its app got LTE instead of slower 3G. This metric showed an even closer grouping: T-Mobile and Verizon tied at 93.67% availability, and AT&T and Sprint were almost even at 88.43% and 87.74%.

OpenSignal analyst Kevin Fitchard commended Sprint’s progress–two years ago, its LTE availability was below 70%. “You cannot knock the improvements that they’ve been making,” he said in an interview Tuesday.

PCMag.com’s “Fastest Mobile Networks” testing, based on automated surveys done in cars across the U.S., found a similar pattern. But a second study based on drive testing, RootMetrics, continues to rank Verizon well above all others, with T-Mobile third and Sprint fourth.