I've never heard of him running an 800 in the thick of the season (July and August) while in his normal 3:26-3:29 shape.
If you know of an instance, do tell.
Lagat certainly has impressive finishing speed. Unfortunately for him, he runs up against El Guerrouj in most cases.
In 2002, for instance, he closed a 3:30 1500 in 52-high. Unfortunately, El Guerrouj was there first.
Coe closed that 1980 Moscow race in 52, and, if I'm not mistaken (i.e., the one he lost), the winning time was not 3:30 but 3:38.
In Athens, of course, Lagat ran 52.03 behnd El G. He also outkicked El Guerrouj in a 3:27.40 winning time in Zurich.
It's not really possible to place Coe's sprint in context given that he never even achieved these speeds for a race (his PR was 3:29.77). Lagat certainly hasn't run 1:41, but he is faster than men like Baala and Ramzi over 1500, guys who have run 1:43-1:44 at 800.
Different eras. Coe would have had enormous difficulty winning those things against someone like El Guerrouj if and when El Guerrouj took off with 900 to go and finished in Coe's PB time. Do you think Coe would be hanging off of El Guerrouj's shoulder, for instance, in a Seville-type race at 3:27 1500 pace? I think not.
You might say the same about Coe running up against Wilson Kipketer. I have doubts that Coe's one-time 1:41 speed would look quite so impressive against a 3-time 1:41, who-knows-how-many-time 1:42 man Kipketer in the last 200 of an 800m race.
Coe was great and still is one of the best ever, but his achievements have been surpassed (not the double 1500 gold, obviously, but time-wise and race-tactic wise, he would not be winning golds in the current aura of the event established by Morceli and El Guerrouj).