New Starbucks Competitor Luckin Coffee has filed to go public on Nasdaq. Anyone heard of this chain before and how good is it actually?

I don't drink coffee, so I can't comment on coffee quality - but here are some interesting facts to note:

Started in June 2017, they went from one store to a current 2,370 stores in 28 cities as of 31st March 2019
16.8m transacting customers and 54% customer repurchase rate in 2018
Apparently the uptick in customers and transactions is spurred by heavy discounts and deals, so it would be interesting to see traction if they sold at full price
They plan to open 200 to 300 outlets a month, putting it on track to overtake Starbucks (which has 3,300 locations in China) by the end of 2019
Where are they different from Starbucks is that they focus on delivery/takeaway coffee, and do not focus on seating space (unlike Starbucks). Lower floor space = lower rent = lower costs
2018: Net revenue of RMB 840.7m (US$125.3m) versus MB250,000m in 2017 with a net loss widening to Rmb1.6bn last year from Rmb56.4m.
For the first quarter of 2019: Net revenue of RMB 478.5m from about RMB 13m a year ago with a net loss of RMB 551.8m from RMB 132.2m

Investors include Singapore' GIC and China International Capital Corp.