Is this the best starting rotation in Astros franchise history?

2018: Verlander, Cole, Charlie Morton, Dallas Keuchel, Lance McCullers Jr.
As good as this season’s group is, last year’s rotation was actually deeper. All five regular starters ended up with double-digit win totals and ERAs under 4.00. It was a virtual Murderer’s Row.
Verlander led the way with 16 wins and a 2.52 ERA, leading the league with 290 strikeouts and leading the majors with a 0.902 WHIP. He ended up finishing second in the Cy Young voting, losing to Tampa’s Blake Snell.
Cole finished fifth in the voting on the strength of 15 wins and a 2.88 ERA with 276 strikeouts. He led the majors with 12.4 strikeouts per nine innings and served as a co-ace along with a future Hall-of-Famer. Not too shabby.
Morton was the third Astros pitcher to strike out 200 batters last season, also notching 15 wins to go along with a 3.13 ERA. He led the majors in winning percentage and earned his first All-Star selection.
Keuchel posted a 12-11 record with a 3.74 ERA, winning his fourth Gold Glove award and leading the majors in total batters faced. Along with Verlander and Cole, he was the third Astros pitcher to throw 200 innings that season.
Finally, McCullers made 22 starts and three relief appearances, compiling a 10-6 record and 3.86 ERA in 128.1 innings. He solidified the fifth starter spot for much of the season, giving the Astros an incredibly deep rotation.
In comparing the two staffs, Morton and Keuchel have essentially been replaced by Greinke and Miley, respectively. Greinke is having a better season ERA-wise than Morton did and is generally a more well-regarded pitcher overall. Keuchel has more accolades than Miley, but Miley is having the better season.
The fifth spot would be the deciding factor. If Peacock can return to match or improve upon the 4.13 ERA he’s posted this season, that could tip the scales in 2019’s favor. Otherwise, 2018 still has a claim to being the best rotation in Astros history.